Tissue Arsenic Concentrations Research Articles

Responses of earthworm Metaphire vulgaris gut microbiota to arsenic and nanoplastics contamination

The growing contamination of arsenic and plastics has severely effects on the soil fauna health, including shifts of gut microbiota community. A few studies have focused on effects of microplastics and metal(loid) in soil and fauna gut microbiome. However, the environmental effect of nanoplastics and arsenic on the earthworm gut microbiota, especially on arsenic biotransformation in the gut, remain largely unknown. Here, a microcosm study was performed to explore the effects of nanoplastics and arsenic on the microbiota characteristics in earthworm Metaphire vulgaris gut using Illumina high throughput sequencing, and to investigate changes in the gut microbiota-mediated arsenic biotransformation genes (ABGs) by using high-throughput quantitative PCR. Our results demonstrated that the concentration of arsenic in the earthworm body tissues after exposure to arsenic and nanoplastics was significantly lower from that with arsenic alone exposure. Moreover, the clearly different bacterial community was observed in the soil compared with the earthworm gut, which was dominated by Proteobacteria, Actinobacteria, and Firmicutes at phylum level. Arsenic exposure significantly disturbed bacterial community structure in the earthworm gut, but exposure to nanoplastics did not induce gut microbiota changes. More interestingly, nanoplastics can relieve adverse effect of arsenic on the gut microbiota possibly by adsorbing arsenic. In addition, a total of 16 ABGs were detected, and predominant genes involved in arsenic reduction and transport process were observed in the earthworm guts. In short, this study provides a new picture of the effects of nanoplastics and arsenic on the gut microbiota and arsenic biotransformation in soil fauna gut.

Concentrations of arsenic in freshwater, estuarine and mangrove clams from the Mekong and Red R. deltas

During 2017-2018 arsenic concentrations in soft tissues of economically important bivalves from the Mekong and the Red R. Deltas were estimated. Freshwater, estuarine and mangroves species in 10 genera from 11 sites were analyzed. Arsenic levels in both freshwater and estuarine clams were below the permissible limits for hazardous substances in fish and fishery products for recommendation of FAO. In the contrary, in mangrove clams Geloina increased levels of As were found. Target hazard quotients and target cancer risk of As was calculated. Arsenic concentrations in the tissues of the Geloina are estimated to pose a rather high total cancer risk to consumers.

Trace metals in striped dolphins (Stenella coeruleoalba) stranded along the Murcia coastline, Mediterranean Sea, during the period 2009–2015.

Mercury (Hg), cadmium (Cd), lead (Pb), selenium (Se) and arsenic (As) concentrations in internal tissues of 72 striped dolphins (Stenella coeruleoalba) from Murcia Region (Mediterranean coastline) have been investigated for the first time. Hg showed the highest concentration, followed by Se, Cd, As and Pb. In general, the levels of metal found in this study were similar to those described in similar studies in the Mediterranean Sea. However, in some adult specimens, Hg liver concentrations were related with toxic effects in cetacean. A significant correlation was observed with age, likewise between Se and Hg and Cd in tissues, which agree with detoxify effect attributed to Se through inert complex formation. Molar ratio Hg:Se in liver was close to 1:1 in some specimens, which would indicate overload of the Hg-Se detoxify function and compromised health. These results could contribute to a better knowledge of the distribution of these persistent pollutants in the Mediterranean Sea.

Relationship between arsenic accumulation in tissues and hematological parameters in mullet caught in Faro Lake: a preliminary study.

The authors investigated the arsenic (As) accumulation in different tissues (muscle, gill, liver, stomach, and intestine) and the possible correlation between tissue concentration and hematological parameters in mullet (Mugil cephalus Linnaeus, 1758) caught in Faro Lake (Messina, Sicily, Italy). On all fish, hematological analyses of blood samples, measurement of biometric indices, and the removal of the muscles, gills, liver, stomach, and intestine for the determination of arsenic concentration were performed. A hemogram was performed to find effects of arsenic concentration in tissues on hematological variables. One-way analysis of variance showed significant differences of arsenic concentration in different tissues, with higher values in the gill. The correlation between hematological parameters and tissue arsenic concentration showed a statistical significance for red blood cell (RBC), hemoglobin concentration (Hb), and hematocrit (Hct) with the liver As concentration. Biometric indices (weight, length, and fork length) showed a significant correlation with As concentration of the muscle and liver also. Our results indicate the role of some hematological parameters as biomarkers useful to monitoring anthropogenic load of arsenic in water and sediment, because variations of these parameters represent one of the effects that arsenic exposure can have on fish.

Heavy Metals Analysis in Human Body (Toenail, Fingernail and Hair Samples) and Drinking Waters of Santa Fe Region, Argentina

This study provides an insight into a province of Santa Fe region of a developing country, namely San Cristobal and Huanqueros, Argentina and a possible link between arsenic, copper and iron concentration in toenail, fingernail and hair in the population. A multivariate statistical tool, known as Principal Component Analysis (PCA) was applied to explain the behaviour of the elements in toenails, fingernails, drinking waters and hair using multi- base 2013 excel add- ins. Correlation test, error bars, and a 2-factor ANOVA test were employed. Results from one hundred and twenty- nine (n=129) samples of tap well water (n=23), rainwater (n=20), bottled water (n=6) and treated well water (n=80) and each of toenail, fingernail and hair (n=129) samples from the subjects were determined and the results compared with the previous works. Mean, standard deviation, covariance and maximum and minimum for each variable were reported. The hypothesis is to understand if there is a correlation between fingernail and toenail metals levels and make a comparison with previous researches. Results show that a positive correlation exists between fingernail and toenail metals concentrations. Also, the study reveals higher concentrations of arsenic, copper and iron in the samples tissues compared with the values available in the previous works. The elevated levels of these metals may be attributed to the drinking water sources. Since this study highlighted elevated levels of these metals, consumptions of contaminated drinking water should be constantly monitored. Finally, the application of multivariate statistical techniques can provide powerful information on heavy metals bioaccumulation analysis in human and environment.

Root transcripts associated with arsenic accumulation in hyperaccumulator Pteris vittata

Hyperaccumulation of arsenic (As) by brake fern Pteris vittata has been described as an important genetic trait that provides an option for development of a sustainable phytoremediation process for As mitigation. Accumulation of very high concentration of arsenic in above-ground tissues may be the result of arsenic vacuole compartmentalization, but the mechanism(s) of arsenic uptake and transport by underground tissues are largely unknown. In this study, we made an attempt towards understanding the molecular mechanism of As hyperaccumulation in this plant. A time-dependent As accumulation study indicates an exponential accumulation of As from 7 to 30 days of arsenic exposure in fronds, and day 3-7 in roots. Root transcriptome analysis identified 554,973 transcripts. Further, subsets of 824 transcripts were differentially expressed between treated and control samples. Many of the genes of critical As-stress response, transcription factors and metal transporters, biosynthesis of chelating compounds involved in uptake and accumulation mechanisms were identified. The genes that were highly expressed such as cysteine-rich RLK, and ABC transporter G family member 26 needs further studies along with arsenite transmembrane transporter. The analysis of generated transcriptome dataset has provided valuable information and platform for further functional studies.

Increased PIT1 and PIT2 Expression in Streptozotocin (STZ)-induced Diabetic Mice Contributes to Uptake of iAs(V)

ObjectiveThis study aimed to investigate the susceptibility of mice with streptozotocin(STZ)-induced diabetes mellitus (TIDM) to the uptake of pentavalent inorganic arsenic (iAsV) and the possible molecular mechanism. MethodsTIDM was induced in mice by STZ. TIDM and normal mice were treated with 15.0 mg/kg Na2HAsO4·12H2O by intragastric administration. Then, the concentrations of arsenic in various tissues were measured by atomic fluorescence spectrometry. The gene expression levels of Pit1 and Pit2 were quantified by real-time RT-PCR, and their protein levels were detected by Western blotting in mouse heart, kidney, and liver tissues. ResultsThe concentrations of arsenic in STZ-induced TIDM mouse tissues were higher at 2 h after intragastric administration of Na2HAsO4·12H2O. Compared with the levels in normal mice, PIT1 and PIT2, which play a role in the uptake of iAsV, were upregulated in the livers and hearts of TIDM mice. PIT1 but not PIT2 was higher in TIDM mouse kidneys. The upregulation of Pit1 and Pit2 expression could be reversed by insulin treatment. ConclusionThe increased uptake of iAsV in TIDM mouse tissues may be associated with increased PIT1 and/or PIT2 expression.

Evaluation of Distribution and Bioaccumulation of Arsenic by ICP-MS in Tilapia (Oreochromis niloticus) Cultivated in Different Environments

The concentration of arsenic in tissues of tilapia was evaluated and an estimation of the risks associated with the consumption of this fish was done, taking into account the guidelines established by FAO/WHO. The inductively coupled plasma mass spectrometry (ICP-MS) technique in kinetic energy discrimination (KED) mode was employed and certified reference materials were analyzed with recoveries of 101, 110, and 80% from NIST 1640a (trace elements in water), NIST 1566b (oyster tissue), and DORM-3 (fish protein). In the consumable portion (the muscle fish tissue), the average concentration found was 0.030 ± 0.008 µg g-1, which is below the arsenic maximum level established by international regulatory agencies. The average concentration found in the viscera (stomach, gills, and liver) was 0.485 ± 0.225 µg g-1, concluding that the viscera had greater capacity for the bioaccumulation of arsenic. From this study was possible to monitor the arsenic element in different tilapia specimens evidencing its accumulation throughout the body of the fish.

Biological effects of gold mine tailings on the intertidal marine environment in Nova Scotia, Canada

From 1861 to the 1940s, gold was produced from 64 mining districts in Nova Scotia, where mercury amalgamation was the dominant method for the extraction of gold from ore until the 1880s. As a result, wastes (tailings) from the milling process were contaminated by mercury and were high in naturally occurring arsenic. In 2004 and 2005, sediments, water and mollusc tissues were collected from 29 sampling stations at nine former gold mining areas along the Atlantic coastline and were analysed for arsenic and mercury. The resulting data were compared with environmental quality guidelines. Samples indicated high potential risk of adverse effects in the intertidal environments of Seal Harbour, Wine Harbour and Harrigan Cove. Arsenic in Seal Harbour was bioavailable, resulting in high concentrations of arsenic in soft-shell clam tissues. Mercury concentrations in tissues were below guidelines. This paper presents results of the sampling programs and implications of these findings.

Ecological drivers influence the distributions of two cryptic lineages in an earthworm morphospecies

Substantial genetic diversity exists within earthworm morphotypes, such that traditional species designations may be incomplete. It is, however, currently not known whether these different genetic variants show ubiquity or specialty in their distribution across separated sites subject to different climatic, biotic or soil physicochemical factors. Here we report on the results of a survey in which individuals of the Lumbricus rubellus morphotype, a species known to comprise two deeply divergent genetic lineages in England and Wales, were sampled from 26 plots. Sequences from the mitochondrial cytochrome oxidase I gene were used to distinguish lineages for 787 individuals. In conjunction, a range of geographic, climatic, biotic and soil physiochemical variables were also collected for each locality.Genotyping indicated that Lineage A was more common than Lineage B, comprising 58% of the collected L. rubellus. Six site populations comprised only Lineage A, while only a single site comprised entirely Lineage B. The remaining 20 sites contained both lineages. A multivariate ordination of site variables identified major difference between sites were associated with low pH, organic-rich soils in Western wet upland areas and pollutant levels associated with sites in the South. Earthworm genotype (as proportion of Lineage A) was not correlated with either of these major environmental axes. When individual variables of soil pH and the percentage of soil organic matter, which are known to be key driver of soil species distributions, were investigated as single variables significant relationship with lineage frequency were found. Soil organic matter content was significantly negatively correlated with Lineage A proportion, while pH was significantly positively correlated. This lineage preference may be related to lineage metabolism and/or behavioral differences.Measurement of tissue metal concentrations in worms from 17 sites identified a significant site effect in all cases, but a lineage effect only for arsenic (higher Lineage B). Tissue arsenic concentrations varied between lineages, supporting previous observations that there are differences in the way the two lineages have adapted to manage exposure to this metalloid.

Assessment of heavy metals concentration in water, soil sediment and biological tissues of the lesser flamingos in four eastern rift valley lakes

The term heavy metal refers to any metallic chemical element that has a relatively high density and is toxic at low concentrations. This study was conducted in four eastern Rift Valley lakes which included Lakes Oloidien, Crater, Elementaita and Nakuru, to determine the presence and levels of lead, arsenic, cadmium and chromium concentration in water, soil sediments and biological tissues of the Lesser Flamingos (Phoeniconaias minor) and compare with the set standards. As these lakes catchments fall directly within a combination of agricultural and industrial regions, the run-offs and the resulting effluents will make the waters highly prone to chemical contamination. The methodology involved collection of water samples (n=40), sediments samples (n=51) and the Lesser Flamingos (live n= 6; dead n=2) for qualitative and quantitative toxicological analysis. The analysis was done using Graphite Furnace Atomic Absorption Spectrophotometer (GFAAS) model-Specter AA-10 Varian. Lead and arsenic were found to be in high concentration in soil sediments in all four lakes while chromium and cadmium were in low concentration. Soil sediments analysed from the inflow of the Nakuru sewerage drain (1754±22.81 ppb) and rivers to Lake Nakuru (1129±107 ppb) had the highest mean ± SD lead concentration. Arsenic, cadmium, chromium and lead were also observed in bird tissues. Metals in the Lesser Flamingo tissues were below the toxicological levels that are reported in literature to be harmful, except lead which was above the level recommended by the US Environmental Protection Agency. Key words: Heavy metals, lesser flamingo, environment.

Analyzing the quantitative risk and hazard of different waterborne arsenic exposures: case study of Haraz River, Iran

In this study, arsenic concentration of Haraz River water at 20 stations and relative risk and hazard levels regarding ingestion and dermal exposure routes are evaluated. Furthermore, the quantitative threat caused by the consumption of Rainbow trout muscle from the area is also analyzed. The concentration of arsenic increases from upstream areas towards the downstream estuarine zone with a substantial rise in the central part. Arsenic-containing drainage discharged from the Central Alborz coal mine, hot spring spas, as well as municipal (Amol city) and agricultural (numerous rice paddies) land uses that become denser towards downstream are considered as major pollution sources. The inhabitants are not exposed to a significant hazard or risk regarding dermal exposure. However, for the oral ingestion exposure route, all 20 samples present hazard quotient values greater than unity and risk values greater than one in ten thousand. The results show that if the river water is used for drinking, a high-risk status would be imposed on consumers. Finally, the concentration of arsenic in muscle tissues of ten Rainbow trout fish samples was found to range from 0.48 to 1.30 μg/kg of dry weight which is below the allowed daily intake. However, if we consider that lots of other constituents in the total daily intake within the study area contain arsenic, estimated values may be interpreted as a trigger for further health threats.

Comparing trace metal bioaccumulation characteristics of three freshwater decapods of the genus Macrobrachium

Potential sources and kinetics of metal bioaccumulation by the three Macrobrachium prawn species M. australiense, M. rosenbergii and M. latidactylus were assessed in laboratory experiments. The prawns were exposed to two scenarios: cadmium in water only; and exposure to metal-rich mine tailings in the same water. The cadmium accumulation from the dissolved exposure during 7 days, followed by depuration in cadmium-free water for 7 days, was compared with predictions from a biokinetic model that had previously been developed for M. australiense. M. australiense and M. latidactylus accumulated significant tissue cadmium during the exposure phase, albeit with different uptake rates. All three species retained >95% of the bioaccumulated cadmium during the depuration phase, indicating very slow efflux rates. Following exposure to tailings, there were significant (p<0.05) differences in tissue arsenic, cadmium, lead and zinc concentrations among species. Cadmium and zinc concentrations were increased relative to controls for all three species but were not different between treatments (direct/indirect contact with tailings), suggesting these metals were primarily accumulated via the dissolved phase. All species bioaccumulated significantly greater arsenic and lead when in direct contact with mine tailings, demonstrating the importance of an ingestion pathway for these metals. Copper was not bioaccumulated above control concentrations for any species. The differences between the metal accumulation of the three prawns indicated that a biokinetic model of cadmium bioaccumulation for M. australiense could potentially be used to describe the metal bioaccumulation of the other two prawn species, albeit with an over-prediction of 3–9 times. Despite these being the same genus of decapod crustacean, the study highlights the issues with using surrogate species, even under controlled laboratory conditions. It is recommended that future studies using surrogate species quantify the metal bioaccumulation characteristics of each species in order to account for any differences between species.

Physical barriers: an alternative to prevent negative impacts of chemically treated wood

There exists a possibility of leaching out of chemicals along with preservative components from chemically treated wood on exposure to water or moisture. Physical barriers have gained much acceptance in this regard as alternative non-biocidal wood protection method as it is supposed to reduce leaching and subsequent negative impacts of wood preservative components to the organisms in vicinity. Fibreglass reinforced plastic (FRP) and epoxy paint was coated over chromated copper arsenate (CCA) treated rubber wood panels and exposed in Cochin estuary for 18 months. Total wet weight biomass and numerical abundance of five most abundant group of foulers viz. hydroids, polychaetes, crustaceans including wood borers, barnacles and bivalves on these panels were studied. Copper, chromium and arsenic concentration in tissues and shells of barnacles were also analyzed. Results indicated significantly high biomass and numerical abundance of foulers on physically protected panels than untreated and preservative treated ones. Physical barriers significantly reduced accumulation of metals in barnacles indicating possibility of reduced leaching. Study can be considered as a lean to the impact studies conducted world over regarding the use of CCA for marine applications. However, CCA treated rubber wood as core material for FRP boats can be a better option as it poses less adverse effect on organisms in the vicinity.

Ameliorative potential of Tephrosia purpurea extract against arsenic induced toxicity in wistar rats

Aim: The present investigation has been conducted to evaluate the protective activity of Tephrosia purpurea extract (TPE) against arsenic induced toxicity. Materials and Methods: For this study, twenty four wistar albino rats were taken. Control group, group – I rats were given sodium arsenite @ 10 mg/kg and group – II rats were treated with TPE @ 500 mg/kg along with sodium arsenite @ 10 mg/kg (daily oral for 28 days). On 29th day animals were slaughtered and various parameters were determined. Serum biomarkers, haematological parameter analysis and histomorphological examination are carried out with estimation of arsenic concentration in tissues. Results: Oral administration of sodium arsenite @ 10 mg/kg for 28 days resulted in a significant decrease in Hb%, TEC and TLC, significant increase of serum glucose, cholesterol, calcium and significant increase in arsenic accumulation in tissues. Histopathological results of intestine revealed haemorrhagic enteritis along with loss of villi. Treatment with Tephrosia purpurea @ 500 mg/kg significantly decreased the elevated glucose, LDH levels, along with significant increase haematological levels towards normal. There was reduced haemorrhagic enteritis and presence of intact villi, as compared to arsenic treated group. But there was no significant difference in serum calcium, serum cholesterol and arsenic concentration in tissues, when compared with arsenic treated group. Conclusion: The study conclude that supplementation of TPE (500 mg/kg) daily oral for 28 days has shown protection against arsenic induced toxicity by its protective effect.

Arsenic-induced biochemical and genotoxic effects and distribution in tissues of Sprague–Dawley rats

Arsenic (As) is a well documented human carcinogen. However, its mechanisms of toxic action and carcinogenic potential in animals have not been conclusive. In this research, we investigated the biochemical and genotoxic effects of As and studied its distribution in selected tissues of Sprague–Dawley rats. Four groups of six male rats, each weighing approximately 60±2g, were injected intraperitoneally, once a day for 5days with doses of 5, 10, 15, 20mg/kg BW of arsenic trioxide. A control group was also made of 6 animals injected with distilled water. Following anaesthetization, blood was collected and enzyme analysis was performed by spectrophotometry following standard protocols. At the end of experimentation, the animals were sacrificed, and the lung, liver, brain and kidney were collected 24h after the fifth day treatment. Chromosome and micronuclei preparation was obtained from bone marrow cells. Arsenic exposure significantly increased (p<0.05) the activities of plasma alanine aminotransferase–glutamate pyruvate transaminase (ALT/GPT), and aspartate aminotransferase–glutamate oxaloacetate transaminase (AST/GOT), as well as the number of structural chromosomal aberrations (SCA) and frequency of micronuclei (MN) in the bone marrow cells. In contrast, the mitotic index in these cells was significantly reduced (p<0.05). These findings indicate that aminotransferases are candidate biomarkers for arsenic-induced hepatotoxicity. Our results also demonstrate that As has a strong genotoxic potential, as measured by the bone marrow SCA and MN tests in Sprague–Dawley rats. Total arsenic concentrations in tissues were measured by inductively coupled plasma mass spectrometry (ICP-MS). A dynamic reaction cell (DRC) with hydrogen gas was used to eliminate the ArCl interference at mass 75, in the measurement of total As. Total As doses in tissues tended to correlate with specific exposure levels.

EFFECTS OF SELENIUM, IRON AND ZINC SUPPLEMENTATION ON ARSENIC CONCENTRATION IN TISSUES WITH GROSS PATHOLOGY IN LONG EVANS RATS

The study was carried out to know the effects of selenium, iron and zinc supplementation on gross pathology and tissue arsenic concentration in Long Evans rats during the period from August to October 2003. A total of 25, one-month-old male rats were randomly divided into 5 equal groups as A, B, C, D and E. Rats of group A were kept as control without giving any treatment. Rats of groups B, C and D were given normal rat pellet (25 g / rat / day) and in addition to arsenic trioxide (As2O3) @ 400 mg / litre, they were treated with sodium selenite (NaSe) @ 1 mg / litre, ferrous sulfate (FeSO4) @ 150 mg / litre and zinc sulfate (ZnSO4) @ 50 mg / litre respectively while rats of group E were treated with only arsenic trioxide (AS2O3) 400 @ mg / litre drinking water daily for 42 days. All the rats of groups B, C and D showed slight congestion in the liver, spleen, heart and kidney and haemorrhage in stomach and intestine but the rats of group E showed heavy congestion in the liver, spleen, heart and kidney and rose-red inflammation in the stomach and severe haemorrhagic enteritis. Among the treated groups, the rats of groups B (0.0126-0.27 ppm), C (0.03-0.32 ppm) and D (0.04-0.288 ppm) which were supplemented with sodium selenite, ferrous sulfate and zinc sulfate respectively along with arsenic trioxide showed reduced arsenic concentrations in different tissues while the rats of group E treated only with arsenic trioxide showed higher concentrations of arsenic in tissues (0.05-0.4 ppm). The concentration of arsenic in the liver, kidney, spleen, heart, stomach, intestine, muscle and dermis of the treated rats were 0.27-0.40 ppm, 0.06-0.22 ppm, 0.052-0.20 ppm, 0.0126-0.102 ppm, 0.054-0.16 ppm, 0.064-0.176 ppm, 0.028-0.07 ppm and 0.03-0.05 ppm respectively. It may be concluded that supplementation of selenium, iron and zinc reduces the arsenic concentration in tissues like liver, kidney, spleen, heart, intestine, stomach, muscle and dermis of rats as well as lower the tissue damage caused by arsenic. The present results also indicate that arsenic is deposited mainly in liver followed by kidney, spleen, dermis, heart and muscle.

Toxicity of so-called edible hijiki seaweed (Sargassum fusiforme) containing inorganic arsenic

The UK Food Standards Agency and its counterparts in other countries have warned consumers not to eat hijiki (Sargassum fusiforme; synonym Hizikia fusiformis), a Sargasso seaweed, because it contains large amounts of inorganic arsenic. We investigated dietary exposure of hijiki in weaning male F344/N rats fed an AIN-93G diet supplemented with 3% (w/w) hijiki powder for 7weeks, compared with those fed only an AIN-93G diet. Body weight, body temperature, blood and tissue arsenic concentrations, plasma biochemistry and hematological parameters were measured. We found that feeding rats a 3% hijiki diet led to a marked accumulation of arsenic in blood and tissues, and evoked a high body temperature and abnormal blood biochemistry including elevated plasma alkaline phosphatase activity and inorganic phosphorus, consistent with arsenic poisoning. These findings should prompt further investigations to identify the health hazards related to consumption of hijiki and related Sargassum species in humans.

TOXICOCHEMICAL ANALYSIS OF ARSENIC IN BROILER CHICKEN; IMPLICATIONS FOR HUMAN RISK ASSESSMENT

Among the general public, the word „„arsenic” has become almost synonymous with the word„„poison” because of its toxic nature to humans. Although there has been considerable concern about the adverse effect of arsenic present in drinking water, the risks of arsenic in food have received less attention. The main purpose of this study was to estimate the total arsenic concentration in different tissues (breast, liver and heart) of broiler chicken in different brands available in the Sri Lankan market. Graphite furnace atomic absorption spectrometry (GF-AAS) was used subsequent to dry ash preparation with the presence of Mg(NO3)2 as the ashing aid. The accuracy of the technique was evaluated by using spiked chicken breast sample; the percentage recovery of total As was observed as 105.7%. The concentrations of total arsenic in different brands of broiler chicken were found in the ranges of 0.65-0.85, 0.42-0.52 and not detectable-0.08 µg g-1on wet basis with respect to the brands “A”, “B” and “C”. Some of the tested breast tissue samples violated the tolerance limit (0.5 µg g-1) for total residue of arsenic in chicken meat set by the US-FDA. These values are also higher than the values observed in a market study in the United States, during 1991–1996 and lower than the arsenic values reported in Pakistan in 2007. The variation of mean total arsenic concentrations in breasts, liver and heart tissues within the brand “C”, was observed as 0.04, 0.33 and 0.30 µg g-1on wet basis. These observations conclude that liver and heart tissues contain relatively higher amounts of total arsenic than breast tissues.Another purpose of this study was to estimate total and inorganic arsenic ingested by humans through chicken consumption and thereby make implications for human risk assessment. Taking into account observed total arsenic concentrations of breast muscle tissues in this study and 65% from the total as inorganic arsenic, the inorganic and total arsenic ingested by eating chicken was calculated. Considering average levels of chicken consumption as 60 g/person/day, people may ingest as much as 44.90, 28.29 and 2.10 µg of total arsenic/day, which is equivalent to 29.19, 18.39 and 1.37 µg inorganic arsenic/day from brands “A”, “B” and “C”, respectively. For a person weighing 60 kg, the inorganic arsenic intake would be 0.49, 0.31, and 0.02 µg/kg/day and contributes 23.77, 14.60 and 1.09 percentages by chicken alone out of the FAO/WHO tolerable daily intake which is 2.1µg/ kg/day received from all dietary sources. Moreover, arsenic was tested among the cooked chicken breasts which were subjected to different cooking recipes and it was found that the cooked chicken breast tissues had total arsenic closer to 1 µg g-1; none of them were below the maximum permissible level. These studies suggest that the cooking methods do not have any impact on removing arsenic.

Monitoring of risk metals in chub (Leuciscus cephalus L.) from the Svitava and Svratka rivers in the urban area of Brno, Czech Republic

The aim of this study was to assess the impact of the Brno agglomeration on the distribution of risk elements (Pb, Cd, Cu, Zn, As) in tissues of a total of 50 chub (Leuciscus cephalus L.). Contamination by metals was monitored in fish from different sites on the Svitava and Svratka rivers in the urban agglomeration of Brno in 2008. Metal concentration was determined in the muscle, liver and kidney by high-resolution atomic absorption spectrometry. Electrothermic technique was used to assess lead, cadmium and copper concentrations; zinc content was determined by flame technique and arsenic by hydride generation. The highest concentrations of cadmium, lead, arsenic and zinc in individual tissues, ranked in a descending order as follows: kidney &gt; liver &gt; muscle; for copper it was liver &gt; kidney &gt; muscle. The highest concentrations of cadmium, arsenic and zinc were determined in chub kidney from the locality of Kníničky (1.35 ± 0.97, 0.186 ± 0.076, and 299.7 ± 123.4 mg·kg-1 respectively); the highest concentration of lead was on the Svratka before junction (0.28 ± 0.19 mg·kg-1). The highest contamination with risk metals was found in chub from the Svratka. The assessed concentrations have shown minimum participation of the Brno agglomeration in the accumulation of metals. The concentrations of all risk elements in chub from all of the monitored localities do not pose any environmental or health threat. This study updates published data on chub from the Rivers Svitava and Svratka on concentration of risk elements.