[USCC] seaweed composting

Rufus Chaney compost@compostingcouncil.org
Tue Sep 16 21:37:08 2003


Dear USCC Colleagues:

After sending a comment in response to the question about seaweed compost, =
I decided to do a literature search for seaweed and arsenic, and for =
arsenic and compost. I searched Science Citation Index for the last =
several years, which I can now do from my desk with a new  capability =
provided to USDA researchers by the National Agricultural Library. I knew =
there had been a number of papers about seaweed consumption by sheep, and =
transformations of As in poultry litter during composting, etc. And I =
would do a better service to USCC by sharing the literature with you than =
by only sharing my opinion.

These papers show the issue of arsenic and compost is complex. On the one =
had, certain high As feedstocks may not be wise to include in composts. =
And for states where regulators are very sensitive about arsenic (though =
perhaps irrationally so), one may need to be very careful to exclude =
arsenic sources from composts. On the other hand, compost was used in a =
demonstration of revegetation of a toxic gold mine disturbed site in =
France, greatly reducing As dispersal into the environment. There were =
also studies of absorption of As from several seafoods.

After looking at this literature, I still think it would be wise to avoid =
seaweed unless you are lucky enough to be above to collect seaweed that =
has low levels of As.=20

Actually, I first noticed the use of seaweed as a cheap organic fertilizer =
when I was visiting the tip of the Erie Pininsula in South Australia. =
Soils there are commonly Mn or Zn deficient, and I accompanied a research =
team into the field to rate their wheat genotypes for tolerance of low Mn =
soils. While we stopped at a local park on the ocean for lunch, we saw =
local folks filling a trailer with seaweed from the shore. It was free for =
the collection and did contain nutrients. But as you will see in the =
references, using such seaweed as feed for sheep in Scotland caused high =
accumulation of As in sheep. I have only occassionally eaten a food =
seaweed, and don't expect to again.

regards,

Rufus Chaney
Beltsville, MD

"seaweed" and "arsenic" search in Science Citation Index

Raab, A; Genney, DR; Meharg, AA; Feldmann, J 2003. Identification of =
arsenic species in sheep-wool extracts by different chromatographic =
methods. Appl. Organometal. Chem. 17:684-692.
		"Sheep on the island of North Ronaldsay (Orkney, UK) feed =
mostly on seaweed, which contains high concentrations of dimethylated =
arsenoribosides. Wool of these sheep contains dimethylated, monomethylated =
and inorganic arsenic, in addition to unidentified arsenic species in =
unbound and complexed form. Chromatographic techniques using different =
separation mechanisms and detectors enabled us to identify five arsenic =
species in water extracts of wool. The wool contained 5.2 +/- 2.3 mug =
arsenic per gram wool. About 80% of the arsenic in wool was extracted by =
boiling the wool with water. The main species is dimethylarsenic, which =
accounted for about 75 to 85%, monomethylated arsenic at about 5% and the =
rest is inorganic arsenic. Depending on the separation method and =
condition, the chromatographic recovery of arsenic species was between 45% =
for the anion exchange column, 68% for the size exclusion chromatography =
(SEC) and 82% for the cation exchange column. The SEC revealed the =
occurrence of two unknown arsenic compounds, of which one was probably a =
high molecular mass species. Since chromatographic recovery can be =
improved by either treating the extract with CuCl/HCl (CAT: 90%) or longer =
storage of the sample (CAT: 105%), in particular for methylated arsenic =
species, it can be assumed that labile arsenic-protein-like coordination =
species occur in the extract, which cannot be speciated with conventional =
chromatographic methods. It is clear from our study of sheep wool that =
there can be different kinds of 'hidden' arsenic in biological matrices, =
depending on the extraction, separation and detection methods used. Hidden =
species can be defined as species that are not recordable by the detection =
system, not extractable or do not elute from chromatographic columns."

Hansen, HR; Raab, A; Francesconi, KA; Feldmann, J 2003. Metabolism of =
arsenic by sheep chronically exposed to arsenosugars as a normal part of =
their diet. 1. Quantitative intake, uptake, and excretion. Environ. Sci. =
Technol. 37:845-851.
		"Information on the effects of long-term organoarsenical =
consumption by mammals is limited despite the fact that foodstuffs, =
especially seafood, often contain organoarsenicals at very high concentrati=
ons. Here we evaluate the intake, uptake, and excretion (urine and feces) =
of arsenic by sheep that live on North Ronaldsay in the Orkney Islands and =
naturally consume large amounts of arsenosugars through their major food =
source-seaweed. The sheep eat a broad variety of seaweed species, and =
arsenic concentrations were determined in all the species observed eaten =
by the sheep (5.7-74.0 mg kg(-1) dry mass). Because of preference and =
availability, they feed mostly on the seaweed species found to contain the =
highest arsenic concentrations: Laminaria digitata and Laminaria hyperborea=
 (74 +/- 4 mg kg(-1) dry mass). To quantify the arsenic intake by the =
sheep, a feeding experiment reflecting natural conditions as close as =
possible was set up. In the feeding trial, the average daily intake of =
arsenic by 12 ewes was 35 +/- 6 mg (97% of water-extractable arsenic was =
present as arsenosugars) gained from feeding on the two brown algae. To =
test the possible influence of microflora on the metabolism of arsenosugars=
, six of the sheep were adapted to feeding on grass for 5 months before =
the start of the trial (control sheep), and the remaining six sheep were =
kept on their normal seaweed diet (wild sheep). No significant difference =
in seaweed/arsenic intake and arsenic excretion was found between the two =
groups of sheep. The arsenic excreted in the feces represents 13 +/- 10% =
(n =3D 12) of the total consumed, and on the assumption of that, the =
average urinary excretion is estimated to 86%. The main arsenic metabolite =
excreted in urine was dimethylarsinic acid (DMA(V)) (60 +/- 22%) and minor =
amounts of dimethylarsinoylethanol (DMAE), methylarsonic acid (MA(V)),tetra=
methylarsonium ion (TMA(+)), and arsenate (As(V)) together with seven =
unknown arsenic compounds were also excreted. The urinary arsenic =
excretion pattern showed a lag period (>4 h) before significant quantities =
appeared in the urine, an excretion rate that peaked between 4 and 28 h =
after seaweed intake and a relatively slow half-life (17 h) after end of =
intake."

Castlehouse, H; Smith, C; Raab, A; Deacon, C; Meharg, AA; Feldmann, J =
2003. Biotransformation and accumulation of arsenic in soil amended with =
seaweed. Environ. Sci. Technol. 37:951-957.
		"For many coastal regions of the world, it has been common =
practice to apply seaweed to the land as a soil improver and fertilizer. =
Seaweed is rich in arsenosugars and has a tissue concentration of arsenic =
up to 100 mug g(-1). These arsenic species are relatively nontoxic to =
humans; however, in the environment they may accumulate in the soil and =
decompose to more toxic arsenic species. The aim of this study was to =
determine the fate and biotransformation of these arsenosugars in soil =
using HPLC-ICPIVIS analysis. Data from coastal soils currently manured =
with seaweeds were used to investigate if arsenic was accumulating in =
these soils. Long-term application of seaweed increased arsenic concentrati=
ons in these soils up to 10-fold (0.35 mg of As kg(-1) for nonagronomic =
peat, 4.3 mg of As kg(-1) for seaweed-amended peat). The biotransformation =
of arsenic was studied in microcosm experiments in which a sandy (machair) =
soil, traditionally manured with seaweed, was amended with Laminaria =
digitata and Fucus vesiculosus. In both seaweed species, the arsenic =
occurs in the form of arsenosugars (85%). The application of 50 g of =
seaweed to I kg of soil leads to an increase of arsenic in the soils, and =
the dominating species found in the soil pore water were dimethyl-arsinic =
acid (DMA(V)) and the inorganic species arsenate (As(V)) and arsenite =
(As(III)) after the initial appearance of arsenosugars. A proposed =
decomposition pathway of arsenosugars is discussed in which the arsenosugar=
s are transformed to DMA(V) and further to inorganic arsenic without =
appreciable amounts of methylarsonic acid (MA(V)). Commercially available =
seaweed-based fertilizers contain arsenic concentration between 10 and 50 =
mg kg(-1). The arsenic species in these fertilizers depends on the =
manufacturing procedure. Some contain mainly arsenosugars while others =
contain mainly DMA(V) and inorganic arsenic. With the application rates =
suggested by the manufacturers, the application of these fertilizers is 2 =
orders of magnitude lower than the maximum permissible sewage sludge load =
for arsenic (varies from 0.025 kg ha(-1) yr(-1) in Styria, Austria, to 0.7 =
kg ha(-1) yr(-1) in the U.K.), while a direct seaweed application would =
exceed the maximum arsenic load by at least a factor of 2."

Heinrich-Ramm, R; Mindt-Prufert, S; Szadkowski, D 2002. Arsenic species =
excretion after controlled seafood consumption. J. Chromatogr. B778:263-273=
.
		"The influence of controlled consumption of marine fish on =
the urinary excretion of arsenite, arsenate, dimethylarsinic and monomethyl=
arsonic acid (DMA, MMA) was investigated in two experiments. Arsenic =
species were separated by anion-exchange chromatography and detected with =
hydride-technique atomic absorption spectrometry (detection limit 1, 10, =
2, 2 mug/l). Firstly, 13 probands ate different types of seafood after =
having refrained from any seafood for I week. DMA levels rose from 3.4 +/- =
1.3 mug/g creatinine (n =3D 12; a day before seafood) to a mean peak level =
of 28.2 +/- 20.6 mug/g (n =3D 13; 10-23 h after; P < 0.001; max. 77.7  =
g/g). No other species were excreted before the meal, but small amounts of =
arsenite (8.5% positive; max. 1.7  g/g) and MMA (1.2%; 1.6  g/g) within 2 =
days after it (n =3D 82). Consumption of white herring caused the highest =
DMA levels. Secondly, eight probands ingested white herring (dose 3.5 =
g/kg; DMA content 32.1 &PLUSMN; 15.3 ng/g wet weight; n =3D 36). No =
arsenite, arsenate and MMA was found in the urine or in the herring =
tissues. The mean DMA mass excreted after the meal (65.3 &PLUSMN; 22.0  =
g/24 h) was about 6-fold higher than the sum of base DMA excretion (3.0 =
&PLUSMN; 1.7  g/24 h) and the ingested DMA mass (7.9 &PLUSMN; 2.7  g). =
This indicates that the elevated DMA excretion after herring consumption =
is not caused by the metabolism of inorganic arsenic but of other arsenic =
species present in the fish tissue, e.g. arsenobetaine or fat-soluble =
arsenic species."

Raab, A; Hansen, HR; Zhuang, LY; Feldmann, J 2002. Arsenic accumulation =
and speciation analysis in wool from sheep exposed to arsenosugars. =
Talanta 58:67-76.
		"Wool or hair fibre is a metabolically dead material after =
it has left the epidermis. During growth the fibre in the root is a =
metabolically very active organ, which is highly influenced by the health =
status of the living being. Arsenic is one of the elements that is easily =
taken up by the cells of the root and stored in the fibre afterwards. Here =
we show that arsenic can quantitatively be extracted by boiling the wool =
fibre or hair in water. The high intake of arsenic species by the sheep of =
North Ronaldsay (the seaweed-eating sheep) leads to a high arsenic =
concentration in wool (mean 5.2 +/- 2.3 mug g(-1)). The wool of lambs of =
these sheep, which are not exposed to seaweed, contains about 10 times =
less arsenic, which is still elevated compared to uncontaminated wool. The =
arsenic species identified in wool extract are arsenite (As(Ill)), =
arsenate (As(V)), monomethylarsonic acid (MMA(V)) and monomethylarsonious =
acid (MMA(Ill)) as minor species. The major species is dimethylated =
arsenic DMA in its tri- and pentavalent form (dimethylarsinous acid =
(DMA(III)) and dimethylarsinic acid (DMA(V))) accounting for 85% of the =
specified arsenic in the wool which reflects the amount of dimethylated =
species (i.e. the arsenoribofuranosides) taken up by seaweed being the =
main food source of the sheep, However, there are unknown arsenic species =
in the extract, which are not eluting from a strong anion exchange column. =
In vitro incubation experiments with this kind of wool showed that it has =
reducing properties but no demethylation was recorded. The absorption =
ability of the wool for methylated arsenic species is negligible, while =
inorganic arsenic is easier to be absorbed in the fibre (11-17%). This =
means that the species integrity is only guaranteed in terms of the degree =
of methylation but not in terms of their redox status."

Sakurai, T 2002. Biological effects of organic arsenic compounds in =
seafood. Appl. Organometal. Chem. 16:401-405.
		"This review describes the results of our recent experiment=
s concerning the in vitro biological effects of water-soluble organic =
arsenic compounds contained in seafood in murine immune effector cells =
using synthetic pure materials. A dimethyl organic arsenic compound in =
seaweed, viz. an arsenosugar, was weakly cytotoxic in murine alveolar =
macrophages during a 72 h incubation (50% lethal concentration in vitro, =
LC50 =3D 8 mmol dm(-3)); conversely, it increased the cell viability of =
peritoneal macrophages at an optimal dose of 5 mmol dm(-3). Trimethyl =
arsenic compounds in marine animals, arsenocholine and arsenobetaine, were =
less toxic in murine splenocytes, thymocytes, Peyer's patch lymphocytes, =
peritoneal macrophages and alveolar macrophages in vitro, even over 10 =
mmol dm(-3). Interestingly, they significantly increased the cell =
viability of immature bone marrow cells at doses over 100 mumol dm(-3), =
and induced the maturation of bone marrow cells especially into granulocyte=
s. The tetramethyl arsenic compound, tetramethylarsonium hydroxide, =
isolated from some lower marine animals had no in vitro cytolethality on =
murine immune effector cells. Taken together, organic arsenic compounds in =
seafood are not very toxic in living systems."

Hsueh, YM; Hsu, MK; Chiou, HY; Yang, MH; Huang, CC; Chen, CJ 2002. Urinary =
arsenic speciation in subjects with or without restriction from seafood =
dietary intake.=20
Toxicol. Lett. 133:83-91.
		"In order to understand whether ingestion of seafood =
affects the urinary arsenic metabolites. About 42 women and 36 men were =
recruited from the students, parents and teachers in Taipei Medical =
University and National Taiwan University. The study subjects were =
interviewed about dietary habits, cigarette smoking habits, drug and =
vitamin intake, and consumption of seafood. Urine samples were collected =
from study subjects before and after refraining from eating seafood for 3 =
days, respectively. The urine samples were frozen at -20 degreesC =
separated by high-performance liquid chromatography (HPLC), and on line =
linked to hydride generator atomic absorption spectrometry (HGAAS) to =
quantify the levels of various species of inorganic arsenic and its =
metabolites. The levels of arsenite (AsIII), arsenate (AsV), monomethylarso=
nic acid (MMA), dimethylarsinic acid (DMA), total inorganic arsenic =
metabolites, inorganic arsenic percent, MMA,percent and DMA percent were =
similar before and after refraining from eating seafood for 3 days. The =
frequencies of fish, shellfish and seaweed dietary intake were not =
significantly correlated with urinary arsenic species."

Gamble, BM; Gallagher, PA; Shoemaker, JA; Wei, X; Schwegel, CA; Creed, JT =
2002. An investigation of the chemical stability of arsenosugars in =
simulated gastric juice and acidic environments using IC-ICP-MS and =
IC-ESI-MS/MS. Analyst 127:781-785.
		"A more quantitative extraction of arsenic-containing =
compounds from seafood matrices is essential in developing better dietary =
exposure estimates. More quantitative extraction often implies a more =
chemically aggressive set of extraction conditions. However, these =
conditions may result in undesirable chemical changes in the native =
arsenicals which may further complicate the toxicological risk assessment. =
This balance between quantitative extraction and species-specific =
integrity may be best addressed by using simulated gastric juice as an =
extraction solvent to mimic 'bioavailability'. This, conceptually, should =
extract the bioavailable fraction and induce any chemical changes that =
would occur because of ingestion. The most chemically labile species =
associated with seafood are thought to be the arsenosugars and for this =
reason their chemical stability is investigated in this study. Four =
arsenosugars (3-[5'-deoxy-5'-(dimethylarsinoyl)-beta-ribofuranosyloxy]-2-hy=
droxypropylene glycol, As(328); 3-[5'-deoxy-5'-(dimethylarsinoyl)-beta-ribo=
furanosyloxy]-2-hydroxypropanesulfonic acid, As(392); 3-[5'-deoxy-5'-(dimet=
hylarsinoyl)-beta-ribofuranosyloxy]-2-hydroxypropyl hydrogen sulfate, =
As(408); and 3-[5'-deoxy-5'-(dimethylarsinoyl)-beta-ribofuranosyloxy]-2-hyd=
roxypropyl-2,3-hydroxypropyl phosphate, As(482)) were isolated from =
seaweed extracts and subjected to simulated gastric juice and acidic =
conditions which mimic the stomach's pH of 1.1. Three acid solutions were =
used to test the chemical stability of the arsenosugars: simulated gastric =
juice, 78 mM nitric acid and 78 mM hydrochloric acid. The composition of =
the solutions was monitored over time (up to 48 h) using IC-ICP-MS for =
detection. The arsenosugars were found to degrade at the rate of 1.4% per =
h at 38 degreesC and 12.2% per h at 60 degreesC. The plots of percent =
conversion versus time were found to be independent of the starting =
arsenosugar and all had r(2) values of greater than 0.97. A single common =
degradation product was observed in all the stability studies. A mass =
balance between the starting arsenosugar (As(392), As(408) and As(482)) =
and the degradation product was conducted with each set of experiments. =
This mass balance indicated that the degradation process did not produce =
any unchromatographable species. This degradation product was tentatively =
identified as As(254) as determined by ESI-MS/MS spectral data. An acid =
hydrolysis mechanism was proposed for the formation of As(254) from each =
of the native arsenosugars by hydrolysis at the C-L carbon on the ribose =
ring."

Van Hulle, M; Zhang, C; Zhang, XR; Cornelis, R 2002. Arsenic speciation in =
chinese seaweeds using HPLC-ICP-MS and HPLC-ES-MS. Analyst 127:634-640.
		"Three common Chinese edible seaweeds, one brown (Laminaria=
 japonica) and two red (Porphyra crispata and Eucheuma denticulatum), were =
examined for their total arsenic content. The As species were extracted =
with yields of 76.4, 69.8 and 25.0%, respectively. Anion-exchange and =
cation-exchange high-performance liquid chromatography (HPLC) in combinatio=
n with inductively coupled plasma mass spectrometry (ICP-MS) were used for =
the separation of the different arsenic species in two of the three =
seaweed extracts (Laminaria and Porphyra). The main arsenic species in the =
algal extracts are arseno sugars, although it has been shown that the =
Laminaria seaweed contains significant amounts of dimethylarsinic acid =
(DMA). HPLC was coupled with electrospray mass spectrometry (ES-MS) for =
structural confirmation of the arsenic species. The mass spectrometer =
settings for the arseno sugars were optimised using standards. The =
conclusions drawn on the basis of HPLC-ICP-MS were confirmed by the =
HPLC-ES-MS data. The HPLC-ES-MS method is capable of determining both =
arseno sugars and DMA in the seaweeds. The unknown compounds seen in the =
HPLC-ICP-MS chromatogram of Laminaria could not be ascribed to trimethylars=
enic oxide or tetramethylarsonium ion."

Almela, C; Algora, S; Benito, V; Clemente, MJ; Devesa, V; Suner, MA; =
Velez, D; Montoro, R 2002. Heavy metal, total arsenic, and inorganic =
arsenic contents of algae food products. J. Agric. Food Chem. 50:918-923.
		"The total arsenic, inorganic arsenic, lead, cadmium, and =
mercury contents of 18 algae food products currently on sale in Spain were =
determined. The suitability of the analytical methodologies for this type =
of matrix was confirmed by evaluating their analytical characteristics. =
The concentration ranges found for each contaminant, expressed in =
milligrams per kilogram of dry weight, were as follows: total arsenic, =
2.3-141; inorganic arsenic, 0.15-88; lead, <0.05-1.33; cadmium, 0.03-1.9; =
and mercury, 0.004-0.04. There is currently no legislation in Spain =
regarding contaminants in algae food products, but some of the samples =
analyzed revealed Cd and inorganic As levels higher than those permitted =
by legislation in other countries. Given the high concentrations of =
inorganic As found in Hizikia fusiforme, a daily consumption of 1.7 g of =
the product would reach the Provisional Tolerable Weekly Intake recommended=
 by the WHO for an average body weight of 68 kg. A more comprehensive =
study of the contents and toxicological implications of the inorganic As =
present in the algae food products currently sold in Spain may be =
necessary, which might then be the basis for the introduction of specific =
sales restrictions."

Feldmann, J; John, K; Pengprecha, P 2000. Arsenic metabolism in seaweed-eat=
ing sheep from Northern Scotland. Fres. J. Anal. Chem. 368:116-121.
		"Cation exchange and anion exchange liquid chromatography =
were coupled to an ICP-MS and optimised for the separation of 13 different =
arsenic species in body fluids (arsenite, arsenate, dimethylarsinic acid =
(DMAA), monomethylarsonic acid (MMAA), trimethylarsine oxide (TMAO), =
tetramethylarsonium ion (TMA), arsenobetaine (AsB), arsenocholine (AsC), =
dimethylarsinoyl ethanol (DMAE) and four common dimethylarsinoylribosides =
(arsenosugars). The arsenic species were de;ermined in seaweed extracts =
and in the urine and blood serum of seaweed-eating sheep from Northern =
Scotland. The sheep eat 2-4 kg of seaweed daily which is washed ashore on =
the most northern Island of Orkney. The urine, blood and wool of 20 North =
Ronaldsay sheep and kidney, liver and muscle from Il sheep were sampled =
and analysed for their arsenic species, in addition five Dorset Finn =
sheep, which lived entirely on grass, were used as a control group. The =
sheep have a body burden of approximately 45-90 mg arsenic daily. Since =
the metabolism of arsenic species varies with the arsenite and arsenate =
being the most toxic, and or,organoarsenic compounds such as arsenobetaine =
the least toxic compounds, the determination of the arsenic species in the =
diet and their body fluids are important. The major arsenic species in =
their diet are arsenoribosides. The major metabolite excreted into urine =
and blood is DMAA (95 +/- 4.1%) with minor amounts of MMAA, riboside X, =
TMA and an unidentified species. The occurrence of MMAA is assumed to be a =
precursor of the exposure to inorganic arsenic, since demethylation of =
dimethylated or trimethylated organoarsenic compounds is not known (max. =
MMAA concentration 259 mu g/L). The concentrations in the urine (3179 +/- =
2667 mu g/L) and blood (44 +/- 19 mu g/kg) are at least two orders of =
magnitude higher than the level of arsenic in the urine of the control =
sheep or literature levels of blood for the unexposed sheep. The tissue =
samples (liver: 292 +/- 99 mu g/kg kidney: 565 +/- 193 mu g/kg, muscle: =
680 +/- 224 mu g/kg) and wool samples (10470 +/- 5690 mu g/kg) show =
elevated levels which are also 100 times higher than the levels for the =
unexposed sheep."

van Netten, C; Cann, SAH; Morley, DR; van Netten, JP 2000. Elemental and =
radioactive analysis of commercially available seaweed. Sci. Total. =
Environ. 255:169-175.=20
		"Edible seaweed products have been used in many countries, =
specifically Japan, as a food item. Recently these products have become =
popular in the food industry because of a number of interesting medicinal =
properties that have been associated with certain edible marine algae. =
Very little control exists over the composition of these products, which =
could be contaminated with a number of agents including heavy metals and =
certain radioactive isotopes. Fifteen seaweed samples (six local samples =
from the coast of British Columbia, seven from Japan, one from Norway and =
one undisclosed) were obtained. All samples were analyzed for multiple =
elements, using ICP mass spectrometry and for radioactive constituents. It =
was found that six of eight imported seaweed products had concentrations =
of mercury orders of magnitude higher than the local products. Lead was =
found at somewhat higher concentrations in only one local product. =
Laminaria japonica had the highest level of iodine content followed by =
Laminaria setchellii from local sources. Only traces of cesium-137 were =
found in a product from Norway and radium-226 was found in a product from =
Japan. Arsenic levels were found to be elevated. In order to estimate the =
effect of these levels on health, one needs to address the bioavalability =
and the speciation of arsenic in these samples."

Lai, VWM; Cullen, WR; Ray, S 1999. Arsenic speciation in scallops. Marine =
Chem. 66:81-89.=20
		"The arsenic species present in the muscle and the gonad =
of scallops collected near Newfoundland were characterized by using high =
performance liquid chromatography-inductively coupled plasma-mass =
spectrometry (HPLC-ICP-MS). The adductor muscle of the scallops (2.1-9.4 =
mu g As g(-1)) contains arsenobetaine (AsB) as the major water-soluble =
arsenic compound. The gonads of the scallops (7.3-44.1 mu g As g(-1)) =
contain dimethylarsinoylriboside derivatives as the major arsenic =
compound, as well as lower amounts of AsB. No inorganic arsenic species =
was detected in the sample extracts indicating that consumption of the =
scallops poses little human risk."

Luong, KVQ; Nguyen, LTH 1999. Organic arsenic intoxication from bird's =
nest soup. Am. J. Med. Sci. 317:269-271.=20
		Objective: To present a case of organic arsenic intoxicatio=
n after consumption of bird's nest soup in a Vietnamese patient.
		Method: We have described the clinical picture of a =
patient with organic arsenic intoxication, and high levels of urine =
arsenic after consumption of bird's nest soup.
		Result: Withdrawal of bird's nest soup coincided with a =
decrease in urinary arsenic levels and the disappearance of peripheral =
neuropathy.
		Conclusion: This case illustrates the environmental =
contamination of bird's nest soup with organic arsenic. A prompt removal =
of the source from the diet resulted in clinical improvement.=20

Ma, MS; Le, XC 1998. Effect of arsenosugar ingestion on urinary arsenic =
speciation. Clin. Chem. 44:539-550.
		"We developed and evaluated a method for the determination =
of mu g/L concentrations of individual arsenic species in urine samples. =
We have mainly studied arsenite [As(III)], arsenate [As(V)], monomethylarso=
nic acid (MMAA), and dimethylarsinic acid (DMAA) because these are the =
most commonly used biomarkers of exposure by the general population to =
inorganic arsenic and because of concerns over these arsenic species on =
their toxicity and carcinogenicity. We have also detected five unidentified=
 urinary arsenic species resulting from the metabolism of arsenosugars. We =
combined ion pair liquid chromatography with on-line hydride generation =
and subsequent atomic fluorescence detection (HPLC/HGAFS). Detection =
limits, determined as three times the standard deviation of the baseline =
noise, are 0.8, 1.2, 0.7, and 1.0 mu/L arsenic for arsenite, arsenate, =
MMAA, and DMAA, respectively. These correspond to 16, 24, 14, and 20 pg of =
arsenic, respectively, for a 20-mu L sample injected for analysis. The =
excellent detection limit enabled us to determine trace concentrations of =
arsenic species in urine samples from healthy subjects who did not have =
excess exposure to arsenic. There was no need for any sample pretreatment =
step. We used Standard Reference Materials, containing both normal and =
increased concentrations of arsenic, to validate the method. Interlaborator=
y studies with independent techniques also confirmed the results obtained =
with the HPLC/HGAFS method. We demonstrated an application of the method =
to the determination of arsenic species in urine samples after the =
ingestion of seaweed by four volunteers. We observed substantial increases =
of DMAA concentrations in the samples collected from the volunteers after =
the consumption of seaweed. The increase of urinary DMAA concentration is =
due to the metabolism of arsenosugars that are present in the seaweed. Our =
results suggest that the commonly used biomarkers of exposure to inorganic =
arsenic, based on the measurement of arsenite, arsenate, MMAA, and DMAA, =
are not reliable when arsenosugars are ingested from the diet."



"arsenic" & "compost" search:
Garbarino, JR; Bednar, AJ; Rutherford, DW; Beyer, RS; Wershaw, RL 2003. =
Environmental fate of roxarsone in poultry litter. I. Degradation of =
roxarsone during composting. Environ. Sci. Technol. 37:1509-1514.
		"Roxarsone, 3-nitro-4-hydroxyphenylarsonic acid, is an =
organoarsenic compound that is used extensively in the feed of broiler =
poultry to control coccidial intestinal parasites, improve feed efficiency,=
 and promote rapid growth. Nearly all the roxarsone in the feed is =
excreted unchanged in the manure. Poultry litter composed of the manure =
and bedding material has a high nutrient content and is used routinely as =
a fertilizer on cropland and pasture. Investigations were conducted to =
determine the fate of poultry-litter roxarsone in the environment. =
Experiments indicated that roxarsone was stable in fresh dried litter; the =
primary arsenic species extracted with water from dried litter was =
roxarsone. However, when water was added to litter at about 50 wt % and =
the mixture was allowed to compost at 40 degreesC, the speciation of =
arsenic shifted from roxarsone to primarily arsenate in about30 days. =
Increasing the amount of water increased the rate of degradation. =
Experiments also suggested that the degradation process most likely was =
biotic in nature. The rate of degradation was directly proportional to the =
incubation temperature; heat sterilization eliminated the degradation. =
Biotic degradation also was supported by results from enterobacteriaceae =
growth media that were inoculated with litter slurry to enhance the biotic =
processes and to reduce the concomitant abiotic effects from the complex =
litter solution. Samples collected from a variety of litter windrows in =
Arkansas, Oklahoma, and Maryland also showed that roxarsone originally =
present had been converted to arsenate."

Zubillaga, MS; Lavado, RS 2003. Stability indexes of sewage sludge compost =
obtained with different proportions of a bulking agent. Commun. Soil Sci. =
Plant Anal. 34:581-591.
		"The aim of using wastes in agriculture is to achieve a =
sustainable cycle in which these wastes will turn into organic sources in =
agricultural production. The specific objective was to study the compositio=
n of compost made with different sewage sludge/bulking agent ratios and to =
establish the most suitable stability or maturity analytical index for the =
compost. Three compost piles. with different volume proportions (biosolids:=
 sawdust) were performed. Measurements of pH, cationic-exchange capacity =
(CEC), total carbon (Ct), total nitrogen (Nt), ignition losses (IL), =
dissolved organic carbon (DOC), humic (HA), and fulvic acids (FA) were =
conducted. Microbial respiration was measured in the first and last =
thermophilic stage. Heavy metals [chromium (Cr), nickel (Ni), lead (Pb), =
zinc (Zn), copper (Cu), mercury (Hg), silver (Ag), arsenic (As), barium =
(Ba), selenium (Se), and cadmium (Cd)] were determined at the end of =
composting. The ratios used did not influence the compost properties since =
no differences were found either in the composition of final product or in =
the time required to achieve a mature compost. The pH, CEC/Ct, Ct/Nt, and =
IL% did not indicate degree of stability or maturity of compost. The HA =
and FA trials did not allow to establish the degree of the humification =
process. The Ct, Nt, and DOC clearly indicated the end stage in the =
compost piles maturity. These assessments were achieved after two months =
of processing, reaching stability with the following values: 3.5 and 5 g =
kg(-1) for the Ct, 0.25 and 0.38 g kg(-1) for Nt and 0.03 g kg(-1) for =
DOC. The respiration activity decreased by 70%to 80% at the end of the =
thermophilic stage. The level of heavy metals, measured when the study was =
over, did not reach the highest values permitted by current regulations."

Mench, M; Bussiere, S; Boisson, J; Castaing, E; Vangronsveld, J; Ruttens, =
A; De Koe, T; Bleeker, P; Assuncao, A; Manceau, A 2003. Progress in =
remediation and revegetation of the barren Jales gold mine spoil after in =
situ treatments. Plant Soil 249:187-202.=20
		"A series of single extractions and short-term plant tests =
were performed in order to test a variety of inexpensive mineral amendments=
 for the in situ inactivation of trace elements on the fine-grained spoil =
of the former gold mine of Jales, Portugal. Based on the results of these =
tests, mesocosms (lysimeters) were constructed and a small-scale semi-field=
 trial was carried out since 1998. The long-term effect of steelshots (SS, =
iron grit), beringite (B), and municipal compost (C) as spoil amendments =
was investigated. Vegetation establishment on the treated spoils was =
successful with Holcus lanatus L. in year 1 and Pinus pinaster Ait. in =
year 2. Therefore, a detailed monitoring program was implemented for =
determining the sustainability of trace elements in situ inactivation by C =
(5%), CB (5% compost combined with 5% beringite), CSS (5% compost combined =
with 1% steelshots), and CBSS (5% compost combined with 5% beringite and =
1% steelshots) treatments (all amendments are expressed by soil dry =
weight) and of the revegetation. After 3 years, revegetation was excellent =
in the CSS treatment, and successful for the CBSS. Volunteer plant species =
became established in treated spoils during year 2. In contrast, the trees =
planted on the C treated spoil declined from year 2 and some died. In year =
3, the trees on the CB treatment started to decline. Arsenic and zinc =
exposure are suggested to explain the negative effects on pine growth. In =
agreement with results of single extractions, compost addition in the =
spoil increased long-term arsenic percolation. Lead leaching was also =
enhanced. The CBSS and CSS treatments were the most effective for limiting =
water-soluble As and decreasing long-term metal leaching."

[Anon] 2002. Effect of compost in reducing arsenic leaching into groundwate=
r. BioCycle 43(5):10-10.

Lin, HT; Wang, MC; Li, GC 2002. Effect of water extract of compost on the =
adsorption of arsenate by two calcareous soils. Water Air Soil Pollut. =
138:359-374.=20
		"The increasing mobility of arsenate will increase its =
leaching potential to groundwater and uptake by plants. The mobility of =
arsenate in soils is related to the competitive adsorption with other =
substances. The effect of organic substances on the adsorption of arsenate =
by soils was evaluated using the water extract of compost (WEC) as a =
complex anion source in a batch experiment. Two calcareous slate alluvial =
soils, Chiwulan and Shuipientou, with higher arsenic contents of 23.7 and =
12.9 mg kg(-1), respectively, were used. The Langmuir equation has been =
used to describe successfully the As adsorption isotherm for the two =
soils. The maximum adsorption of As was 6.098 and 4.785 mumol g(-1) for =
Chiwulan and Shuipientou soils, respectively. There was competitive =
adsorption for binding sites on the soils between arsenate oxyanions and =
organic anions derived from the dissolved organic carbon (DOC) of WEC. =
Different critical pH values were for arsenate addition related to =
arsenate adsorption on both soils in the absence of DOC of WEC but not in =
the presence of DOC of WEC. The soil properties related to arsenate =
adsorption by the two soils may govern the critical pH values."

Beauchamp, CJ; Charest, MH; Gosselin, A 2002. Examination of environmental =
quality of raw and composting de-inking paper sludge. Chemosphere =
46:887-895.
		"Paper sludges were traditionally landfilled or burned. =
Over the years, the use of paper sludges on soils has increased, as well =
as the concerns about their environmental effects. Therefore, the chemical =
characterization of paper sludges and their young (immature) compost =
needed to be investigated, and over 150 inorganic and organic chemicals =
were analyzed in de-inking paper sludge (DPS). In general, nitrogen, =
phosphorus and potassium contents were low but variable in raw DPS and its =
young compost. The contents of arsenic, boron, cadmium, cobalt, chromium, =
manganese, mercury, molybdenum, nickel, lead, selenium, and zinc were also =
low and showed low variability. However, the copper contents were above =
the Canadian compost regulation for unrestricted use and required a =
follow-up. The fatty- and resin acids, and polycyclic aromatic hydrocarbons=
 were the organic chemicals measured at the highest concentrations. For =
resinic acids, care should be taken to avoid that leachates reach aquatic =
life. For polycyclic aromatic hydrocarbons, naphthalene should be followed =
until soil content reaches 0.1 mug g(-1), the maximum allowed for soil use =
for agricultural purposes according to Canadian Environmental Quality =
Guidelines. In young compost, the concentration of these chemical families =
decreased over time and most compounds were below the detection limits =
after 24 weeks of composting. In raw DPS, among the phenol, halogenated =
and monoaromatic hydrocarbons, dioxin and furan, and polychlorinated =
biphenyl families, most compounds were below the detection limits. The raw =
DPS and its young compost do not represent a major threat for the =
environment but can require an environmental follow-up."

Karam, NS; Ereifej, KI; Shibli, RA; AbuKudais, H; Alkofahi, A; Malkawi, Y =
1998. Metal concentrations, growth, and yield of potato produced from in =
vitro plantlets or microtubers and grown in municipal solid-waste-amended =
substrates. J. Plant Nutr. 21:725-739.
		"In vitro plantlets or microtubers (in vitro produced =
tubers) of 'Spunta' potato (Solanum tuberosum L.) were planted in a 3 soil =
: 2 peat moss : 1 sand substrate (by volume) amended with municipal solid =
waste (MSW) compost at 0, 10, 20, or 30 g 4(-1) L pot. Three months later, =
plant growth and tuber yield were evaluated and concentrations of shoot =
and tuber tin (Sn), arsenic (As), copper (Cu), zinc (Zn), nickel (Ni), =
lead (Pb), manganese (Mn), cadmium (Cd), and iron (Fe) were determined. =
Amending with MSW resulted in significant increases in concentrations of =
all tested metals in the substrate. Number of proliferated shoots of =
plants started from rooted plantlets was greatest at 10 g pot(-1) MSW, =
whereas shoot weight of plants started from microtubers was greatest at 10 =
and 20 g pot(-1) MSW. Tuber yield of plants started from rooted plantlets =
or microtubers was greatest at 10 or 30 g pot(-1) MSW, respectively. In =
all instances, amending with MSW at 30 g pot(-1) resulted in significant =
increases in concentrations of all tested metals in shoots and tubers. =
Concentrations of shoot Ni and tuber Zn and Fe for plants started from =
rooted plantlets and concentrations of shoot Fe and tuber As, Cu and Pb =
for plants started from microtubers increased consistently with increasing =
MSW percentage of the substrate. Plants started fi om rooted plantlets =
produced shoots with sufficient Zn, Mn, and Ni concentrations regardless =
of the substrate but with toxic Cu content at 30 g pot(-1) MSW. Plants =
started from microtubers produced shoots with sufficient Mn and Ni =
concentrations regardless of the substrate but with low Zn and deficient =
Cu in unamended substrates. All plants had shoot Fe content higher than =
the sufficiency range. Although there were significant differences in =
concentrations of some nutrients among MSW treatments, no symptoms of =
nutrient toxicity or deficiency were observed. Ln all instances, tested =
elements did not accumulate in tubers to levels hazardous to human health. =
Concentrations of Cd, the most hazardous element, in potato tubers was not =
high enough to pose a threat to human. Our results indicate that there is =
a potential use of MSW in satisfying the needs of potato growth with =
negligible increases in heavy metal concentrations in tubers."