Comparison of hair with nail as index media for biological monitoring of mercury

Mercury in hair and nails was determined with speciation of chemical forms of mercury. Scalp hair and toenails were sampled once and fingernails were sampled three times from the subjects (18 males and 5 females) whose age ranged from 23 to 56 yr. Total mercury (THg) and inorganic mercury (IHg) were determined by Magos' method with modifications. No sex-related differences were found in mercury levels in hair and nails. In the fingernail samples of three different formation periods, THg and IHg concentrations remained almost constant. Among the three kinds of index media, the highest THg concentration was found in scalp hair followed by fingernails and toenails in the order given, whereas IHg concentrations in scalp hair were similar as those in fingernails but were lowest in toenails. The percent inorganic to total mercury was higher in fingernails than in hair and toenails, which is likely to reflect a possible external contamination with IHg in fingernails. The higher THg concentration in scalp hair than in nails may be attributable to the difference in the chemical composition, in particular sulphur content, and in the blood flow during the formation of hair and nails.     

Arsenic levels in blood, urine, and hair of workers applying monosodium methanearsonate (MSMA)

Uptake and excretion of total arsenic from monosodium methanearsonate (MSMA) in workers who applied the herbicide was followed during the spraying season. Urine, blood, and hair samples were collected and air samples were taken from the workers' breathing zone. Arsenic concentrations in air samples ranged from 0.001-1.086 micrograms/m3. Blood and urine arsenic values ranged from 0.0-0.2 mg/L and 0.002-1.725 mg/L, respectively. The geometric mean arsenic concentration in urine increased during the week but returned to base levels on weekends. Hair arsenic concentrations ranged from 0.02-358.0 mg/kg, increased during the spraying season, and returned to pre-season levels once herbicide application ceased. Three workers had higher than normal pre-exposure hair values. However, only one of the three workers had consistently above normal values throughout the study period.     

石门雄黄矿地区居民砷暴露研究

目的：研究砷污染地区居民砷暴露水平的分布特征。方法：分析污染区和对照区环境样品和居民头发砷含量。结果：污染区三个村土壤砷含量８４．１７～２９６．１９ｍｇ／ｋｇ。河水砷含量达０．５～１４．５ｍｇ／Ｌ，井水、自来水、食物含砷量一般符合国家卫生标准。砷摄入量１９５～１１２９μｇ／ｄ。居民头发砷含量中位数为０．９７２～２．４５９μｇ／ｇ。发砷值随年龄增加而增加。结论：石门雄黄矿附近地区河水砷污染严重，以河水为饮用水源的居民砷暴露水平达到甚至超过国内外重大慢性砷中毒案例的暴露水平，应引起重视     

Surveillance on chronic arsenic exposure in the Mekong River basin of Cambodia using different biomarkers

Thousands of Cambodia populations are currently at high risks of both toxic and carcinogenic effects through drinking arsenic-rich groundwater. In order to determine and assess the use of arsenic contents in different biological samples as biomarkers of chronic arsenic exposure from drinking arsenic-rich groundwater in Cambodia, individual scalp hair, fingernail and toenail were collected from three different provinces in the Mekong River basin of Cambodia. After washing and acid-digestion, digestate was analyzed for total arsenic by an inductively coupled plasma mass spectrometry. Chemical analysis of the acid-digested hair revealed that among 270 hair samples cut from Kandal, 78.1% had arsenic content in scalp hair (As_h) greater than the typical As_h (1.00 μg g⁻¹), indicating possible arsenic toxicity. Concurrently, 1.2% and 0.6% were found elevated in Kratie (n = 84) and Kampong Cham (n = 173), respectively. Similarly, the upper end of the ranges for arsenic contents in fingernail (As_fn) and toenail (As_tn) clipped from Kandal (fingernail n = 241; toenail n = 187) were higher than the normal arsenic content in nail (0.43–1.08 μg g⁻¹), however, none was observed elevated in both Kratie (fingernail n = 76, toenail n = 42) and Kampong Cham (fingernail n = 83; toenail n = 52). Significant positive intercorrelations between groundwater arsenic concentration (As_w), average daily dose (ADD) of arsenic, As_h, As_fn and As_tn suggest that As_h, As_fn and As_tn can be used as biomarkers of chronic arsenic exposure from drinking arsenic-rich groundwater, in which As_h is more favorable than As_fn and As_tn due to the ease of sample processing and analytical measurements, respectively.     

Relation between airborne arsenic trioxide and urinary excretion of inorganic arsenic and its methylated metabolites.

The relation between exposure to As2O3 fumes and dust, and the urinary excretion of inorganic arsenic metabolites (monomethylarsonic acid, dimethylarsinic acid, unchanged inorganic arsenic) has been studied in 18 workers from a sulphuric acid producing plant. The concentration of arsenic in the breathing zone of each worker was measured during five consecutive days and urine samples were obtained after one shift and before the next. The collection efficiency of the air sampling system exceeded 95%. The time weighted average exposure (TWA) concentrations of As2O3 ranged from 6 to 502 micrograms As/m3 and were log normally distributed. Although exposure probably occurred by ingestion as well as inhalation, statistically significant correlations (log scales) were found between airborne TWA of As2O3 and the inorganic arsenic metabolites in urine collected immediately after the shift, or just before the next shift. For a TWA of 50 micrograms As/m3, the mean concentration of the sum of the three inorganic arsenic metabolites in a postshift urine sample amounted to about 55 micrograms arsenic/g creatinine (95% confidence interval (95% CI) 47-62). Higher estimates of urinary arsenic reported by other authors are probably due either to the influence of dietary organoarsenicals when total arsenic is measured in urine or to a low retention efficiency of the air sampling system for As2O3 in the vapour phase.     

Relation between airborne arsenic trioxide and urinary excretion of inorganic arsenic and its methylated metabolites.

The relation between exposure to As2O3 fumes and dust, and the urinary excretion of inorganic arsenic metabolites (monomethylarsonic acid, dimethylarsinic acid, unchanged inorganic arsenic) has been studied in 18 workers from a sulphuric acid producing plant. The concentration of arsenic in the breathing zone of each worker was measured during five consecutive days and urine samples were obtained after one shift and before the next. The collection efficiency of the air sampling system exceeded 95%. The time weighted average exposure (TWA) concentrations of As2O3 ranged from 6 to 502 micrograms As/m3 and were log normally distributed. Although exposure probably occurred by ingestion as well as inhalation, statistically significant correlations (log scales) were found between airborne TWA of As2O3 and the inorganic arsenic metabolites in urine collected immediately after the shift, or just before the next shift. For a TWA of 50 micrograms As/m3, the mean concentration of the sum of the three inorganic arsenic metabolites in a postshift urine sample amounted to about 55 micrograms arsenic/g creatinine (95% confidence interval (95% CI) 47-62). Higher estimates of urinary arsenic reported by other authors are probably due either to the influence of dietary organoarsenicals when total arsenic is measured in urine or to a low retention efficiency of the air sampling system for As2O3 in the vapour phase.     

Environmental exposure and fingernail analysis of arsenic and mercury in children and adults in a Nicaraguan gold mining community

Gold mining can release contaminants, including mercury, into the environment, and may increase exposure to naturally occurring elements such as arsenic. The authors investigated environmental and human tissue concentrations of arsenic and mercury in the gold mining town of Siuna, Nicaragua. The study involved 49 randomly selected households in Siuna, from whom a questionnaire along with environmental and fingernail samples were collected. Environmental samples indicated that mercury concentrations in drinking water, although generally low, were higher near the mine site. Arsenic concentrations were elevated in water and soil samples, but their distribution was unrelated to the mining site. Mercury concentrations in fingernail samples were correlated with residential proximity to the mine, drinking water concentrations, occupation, and, among children, with soil concentrations. Fingernail arsenic concentrations correlated with drinking water concentrations among adults who consumed higher levels, and with soil concentrations among children. Fingernail analysis helped to identify differential exposure pathways in children and adults. Mercury and arsenic uptake via soil exposure in children warrants further consideration.     

Environmental Exposure and Fingernail Analysis of Arsenic and Mercury in Children and Adults in a Nicaraguan Gold Mining Community

Gold mining can release contaminants, including mercury, into the environment, and may increase exposure to naturally occurring elements such as arsenic. The authors investigated environmental and human tissue concentrations of arsenic and mercury in the gold mining town of Siuna, Nicaragua. The study involved 49 randomly selected households in Siuna, from whom a questionnaire along with environmental and fingernail samples were collected. Environmental samples indicated that mercury concentrations in drinking water, although generally low, were higher near the mine site. Arsenic concentrations were elevated in water and soil samples, but their distribution was unrelated to the mining site. Mercury concentrations in fingernail samples were correlated with residential proximity to the mine, drinking water concentrations, occupation, and, among children, with soil concentrations. Fingernail arsenic concentrations correlated with drinking water concentrations among adults who consumed higher levels, and with soil concentrations among children. Fingernail analysis helped to identify differential exposure pathways in children and adults. Mercury and arsenic uptake via soil exposure in children warrants further consideration.     

Assessing the measurement precision of various arsenic forms and arsenic exposure in the National Human Exposure Assessment Survey (NHEXAS)

Archived samples collected from 1995 to 1997 in the National Human Exposure Assessment Survey (NHEXAS) in U.S. Environmental Protection Agency Region 5 (R5) and the Children's Study (CS) in Minnesota were analyzed for total arsenic, arsenate [As(V)], arsenite, dimethyl arsenic acid (DMA), monomethyl arsenic acid (MMA), arsenobetaine (AsB), and arsenocholine. Samples for the CS included drinking water, urine, hair, and dust; both studies included food (duplicate plate, composited 4-day food samples from participants). Except for AsB and As(V), the levels for As species measured in the food and drinking water samples were very low or nonexistent. The analytical methods used for measuring As species were sensitive to < 1 ppb. During the analysis of food and drinking water samples, chromatographic peaks appeared that contained As, but they did not correspond to those being quantified. Thus, in some samples, the sum of the individual As species levels was less than the total As level measured because the unknown forms of As were not quantified. On the other hand, total As was detectable in almost all samples (> 90%) except for hair (47%), indicating that the analytical method was sufficiently sensitive. Population distributions of As concentrations measured in drinking water, food (duplicate plate), dust, urine, and hair were estimated. Exposures to total As in food for children in the CS were about twice as high as in the general R5 population (medians of 17.5 ppb and 7.72 ppb, respectively). In addition, AsB was the most frequently detected form of As in food eaten by the participants, while As(V) was only rarely detected. Thus, the predominant dietary exposure was from an organic form of As. The major form of As in drinking water was As(V). Spearman (rank) correlations and Pearson (log-concentration scale) correlations between the biomarkers (urine, hair) and the other measures (food, drinking water, dust) and urine versus hair were performed. In the NHEXAS CS, total As and AsB in the food eaten were significantly correlated with their levels in urine. Also, levels of As(V) in drinking water correlated with DMA and MMA in urine. Arsenic levels in dust did not show a relationship with urine or hair levels, and no relationship was observed for food, drinking water, and dust with hair. Urine samples were collected on days 3, 5, and 7 of participants' monitoring periods. Total As levels in urine were significantly associated across the three pairwise combinations--i.e., day 3 versus day 5, day 3 versus day 7, and day 5 versus day 7. Because the half-life of As in the body is approximately 3 days, this suggests that some exposure occurred continually from day to day. This trend was also observed for AsB, suggesting that food is primarily responsible for the continual exposure. DMA and MMA in urine were also significantly correlated but not in all combinations.     

指甲镍含量与接镍水平关系的研究

对某镍业公司不同生产车间空气中镍浓度和工人指甲镍含量进行了测定。共获得空气镍浓度数据５７６个，指甲镍含量数据２４０个。根据生产过程过程和卫生学特征。将所得结果按碎矿压球，电炉转炉、氧化镍焙烧、硫酸镍，汽车修配厂５个观察组进行了分析，看出指甲镍含量与空气镍浓度之间呈现一定的接触水平一反应关系。剔出硫酸镍组数据，仅对镍化合物存在形态相同的其余４个组的进行相关性分析，ｒ＝０．９７２，Ｐ＝０．０２８．本研     

Occupational exposure to chromium, copper and arsenic during work with impregnated wood in joinery shops.

CCA-impregnated timber contains copper, chromium and arsenic (CCA), and occupational exposure to wood dust as well as the CCA compounds may occur in work with such timber. Dust from commercially available impregnated wood has been found to contain hexavalent chromium, which is regarded as a carcinogen. Apart from determinations of the total amounts of the CCA compounds, specific determination of hexavalent chromium is therefore essential. Selective methods have been applied for control of the work environment in six joinery shops. The mean exposure to wood dust was found to be below 1 mg m-3. The mean airborne concentration of arsenic around various types of joinery machines was in the range from 0.54 to 3.1 micrograms m-3. No hexavalent chromium was detected in any samples and no increased concentrations of arsenic were found in urine from the workers. The presence of arsenic in the work-room air must be considered for appropriate assessment of the occupational environment in joinery shops.     

Biological monitoring of occupational exposure to inorganic arsenic

OBJECTIVES: This study was undertaken to assess reliable biological indicators for monitoring the occupational exposure to inorganic arsenic (iAs), taking into account the possible confounding role of arsenicals present in food and of the element present in drinking water. METHODS: 51 Glass workers exposed to As trioxide were monitored by measuring dust in the breathing zone, with personal air samplers. Urine samples at the end of work shift were analysed for biological monitoring. A control group of 39 subjects not exposed to As, and eight volunteers who drank water containing about 45 micrograms/l iAs for a week were also considered. Plasma mass spectrometry (ICP-MS) was used for the analysis of total As in air and urine samples, whereas the urinary As species (trivalent, As3; pentavalent, As5; monomethyl arsonic acid, MMA; dimethyl arsinic acid, DMA; arsenobetaine, AsB) were measured by liquid chromatography coupled with plasma mass spectrometry (HPLC-MS) RESULTS: Environmental concentrations of As in air varied widely (mean 84 micrograms/m3, SD 61, median 40) and also the sum of urinary iAs MMA and DMA, varied among the groups of exposed subjects (mean 106 micrograms/l, SD 84, median 65). AsB was the most excreted species (34% of total As) followed by DMA (28%), MMA (26%), and As3 + As5 (12%). In the volunteers who drank As in the water the excretion of MMA and DMA increased (from a median of 0.5 to 5 micrograms/day for MMA and from 4 to 13 micrograms/day for DMA). The best correlations between As in air and its urinary species were found for total iAs and As3 + As5. CONCLUSIONS: To avoid the effect of As from sources other than occupation on urinary species of the element, in particular on DMA, it is proposed that urinary As3 + As5 may an indicator for monitoring the exposure to iAs. For concentrations of 10 micrograms/m3 the current environmental limit for iAs, the limit for urinary As3 + As5 was calculated to be around 5 micrograms/l, even if the wide variation of values needs critical evaluation and application of data. The choice of this indicator might be relevant also from a toxicological point of view. Trivalent arsenic is in fact the most active species and its measure in urine could be the best indicator of some critical effects of the element, such as cancer.

 

     

Maternal arsenic exposure associated with low birth weight in Bangladesh

OBJECTIVE: To characterize the effects of maternal arsenic exposure on birth weight. METHODS: Hair, toenail, and drinking water samples were collected from pregnant women (n = 52) at multiple time points during pregnancy and from their newborns after birth. Total arsenic was measured using inductively coupled plasma-mass spectrometry. The association between arsenic and birth weight was investigated using linear and logistic regression models. RESULTS: Maternal hair arsenic measured early in pregnancy was associated with decreased birth weight (beta = -193.5 +/- 90.0 g, P = 0.04). Maternal hair and drinking water arsenic levels measured at first prenatal visit were significantly correlated with newborn hair arsenic level (rho = 0.32, P = 0.04 and rho = 0.31, P = 0.04). CONCLUSIONS: Results suggest that maternal arsenic exposure early in pregnancy negatively affects newborn birth weight and that maternal hair provides the best integrated measure of arsenic exposure.     

Airborne arsenic and urinary excretion of arsenic metabolites during boiler cleaning operations in a Slovak coal-fired power plant.

Little information is available on the relationship between occupational exposure to inorganic arsenic in coal fly ash and urinary excretion of arsenic metabolites. This study ws undertaken in a coal-fired power plant in Slovakia during a routine maintenance outage. Arsenic was measured in the breathing zone of workers during 5 consecutive workdays, and urine samples were obtained for analysis of arsenic metabolites--inorganic arsenic (Asi), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA)--prior to the start of each shift. Results from a small number of cascade impactor air samples indicated that approximately 90% of total particle mass and arsenic was present in particle size fractions >/= 3.5 micron. The 8-hr time-weighted average (TWA) mean arsenic air concentration was 48.3 microg/m3 (range 0.17-375.2) and the mean sum of urinary arsenic (SigmaAs) metabolites was 16.9 microg As/g creatinine (range 2.6-50.8). For an 8-hr TWA of 10 microg/m3 arsenic from coal fly ash, the predicted mean concentration of the SigmaAs urinary metabolites was 13.2 microg As/G creatinine [95% confidence interval (CI), 10.1-16.3). Comparisons with previously published studies of exposure to arsenic trioxide vapors and dusts in copper smelters suggest that bioavailability of arsenic from airborne coal fly ash (as indicated by urinary excretion) is about one-third that seen in smelters and similar settings. Arsenic compound characteristics, matrix composition, and particle size distribution probably play major roles in determining actual uptake of airborne arsenic.     

Behavior of the electron spin resonance signals in X-ray irradiated human fingernails for the establishment of a dose reconstruction procedure

The retrospective dosimetry that follows accidental X-ray exposure is becoming more significant for improving radiation diagnosis and treatment. We investigated the dosimetric properties of electron spin resonance (ESR) signals in X-ray irradiated fingernails under conditions that resemble realistic situations. We collected fingernails from 12 Japanese donors between the ages of 30 to 70. The sampled fingernails were utilized for X-ray irradiation, mechanical stimulation and background measurements. We also collected 10 toenails from one of the donors to evaluate their differences from fingernails. Additionally, we prepared 15 samples from two donors to compare the signals generated by γ-rays to those by X-rays. After observing the linear dose–response for both X- and γ-ray irradiated samples, we found that the sensitivity of the air-absorbed dose of γ-ray irradiated samples was identical to that of X-ray irradiated samples. The effect from secondary electrons seemed to be small in fingernails. The inter-individual variation in the sensitivity was no greater than the intra-individual variation. The signal intensities in each measurement fluctuated about the linear response curve, and the size of the fluctuation was dependent on the sample. The average fluctuation corresponded to 1.7 Gy, and the standard deviation was 1.3 Gy. The signal induced by X-rays could be erased by soaking the samples in water and subsequently drying them for four days, which allowed us to estimate the signal intensity prior to the exposure. These characteristics of the ESR signal induced by X-rays facilitate the development of a feasible protocol for fingernail dose reconstruction.     

Surveillance on chronic arsenic exposure in the Mekong River basin of Cambodia using different biomarkers

Thousands of Cambodia populations are currently at high risks of both toxic and carcinogenic effects through drinking arsenic-rich groundwater. In order to determine and assess the use of arsenic contents in different biological samples as biomarkers of chronic arsenic exposure from drinking arsenic-rich groundwater in Cambodia, individual scalp hair, fingernail and toenail were collected from three different provinces in the Mekong River basin of Cambodia. After washing and acid-digestion, digestate was analyzed for total arsenic by an inductively coupled plasma mass spectrometry. Chemical analysis of the acid-digested hair revealed that among 270 hair samples cut from Kandal, 78.1% had arsenic content in scalp hair (As_h) greater than the typical As_h (1.00 μg g⁻¹), indicating possible arsenic toxicity. Concurrently, 1.2% and 0.6% were found elevated in Kratie (n = 84) and Kampong Cham (n = 173), respectively. Similarly, the upper end of the ranges for arsenic contents in fingernail (As_fn) and toenail (As_tn) clipped from Kandal (fingernail n = 241; toenail n = 187) were higher than the normal arsenic content in nail (0.43–1.08 μg g⁻¹), however, none was observed elevated in both Kratie (fingernail n = 76, toenail n = 42) and Kampong Cham (fingernail n = 83; toenail n = 52). Significant positive intercorrelations between groundwater arsenic concentration (As_w), average daily dose (ADD) of arsenic, As_h, As_fn and As_tn suggest that As_h, As_fn and As_tn can be used as biomarkers of chronic arsenic exposure from drinking arsenic-rich groundwater, in which As_h is more favorable than As_fn and As_tn due to the ease of sample processing and analytical measurements, respectively.     

Occupational exposures during routine activities in coal-fueled power plants

Limited information is available on occupational exposures during routine, nonoutage work activities in coal-fueled power plants. This study evaluated occupational exposures to the principal contaminants in the facilities, including respirable dust (coal dust), arsenic, noise, asbestos, and heat stress. The data were collected over a 3-month period, during the summer of 2001, in 5 facilities that were chosen to be representative of the coal-fueled power plants of a large southeastern power-generating company. Each of the facilities was divided into 5 similar exposure groups based on previous exposure assessments and job tasks performed. From 4 of the 5 facilities, 392 air samples and 302 noise samples were collected with approximately 50 respirable coal dust, 32 arsenic, 15 asbestos, and 70 noise samples from each of the 4 plants. One of the previously surveyed facilities was also evaluated for heat stress, and 1 additional coal-fueled power plant was surveyed for a total of 20 personal heat stress samples. Personal monitors and area WBGT monitors were used. Of the nearly 400 air samples collected, only 1 exceeded the allowable occupational exposure value. For the noise samples, 55 (approximately 18%) were equal to or greater than the Occupational Safety and Health Administration (OSHA) 8-hour hearing conservation program level of 85 dBA, and 12 (approximately 4%) were equal to or greater than the OSHA 8-hour permissible exposure level of 90 dBA. Heat stress monitoring at the facilities indicates that 26% of the 1-hour TWAs were exceeded for one or all of the recommended heat stress limits. The data also concluded that some work sites were above the heat stress ceiling values recommended by the National Institute for Occupational Safety and Health (NIOSH). Four of the 20 employees personally monitored exceeded the recommended limits for heart rate or body core temperature. This suggests there is a potential for heat strain if signs and symptoms are ignored. Recommendations are made to better control the heat stress exposure.     

Environmental and occupational exposure to manganese: a multimedia assessment

Methylcyclopentadienyl manganese tricarbonyl (MMT) is an organic additive used in Canada since 1976 as an anti-knock agent in unleaded gasoline. Its combustion leads to the emission of Mn oxides, especially Mn₃O₄. Since no study has assessed the potential risk of chronic exposure to low concentrations resulting from these emissions, the present investigation was undertaken to assess the level of environmental and occupational exposure of the human population. The multimedia exposure of two groups of workers (garage mechanics and blue-collar workers) potentially exposed to different levels of Mn from the combustion of MMT was assessed using personal air samplers, a dietary compilation, water samples at their places of residence, an epidemiological questionnaire and blood and hair samples. Results show that garage mechanics were exposed on average to higher atmospheric Mn at work (0.42 µg/m³) than the blue-collar workers (0.04 µg/m³). However, the contribution of atmospheric Mn to the total absorbed dose was less than 1%, and well below the standards estabished for occupational or environmental exposure; food contributes more than 95% of the multimedia dose. The average whole blood Mn concentrations were similar for the two groups (0.67–0.76 µg/100 ml) and fall within the normal adult range. The average hair Mn concentrations were significantly higher for the garage mechanics (0.66 µg/g) than for the blue-collar workers (0.39 µg/g). The contribution of exogenous Mn versus endogenous Mn is questioned. As judged by the governmental standards or criteria for occupational and non-occupational environments, the current Mn levels in food, water and air may not cause any problems for the workers.     

Biomarkers of mercury exposure in two eastern Ukraine cities

This study evaluates biomarkers of mercury exposure among residents of Horlivka, a city in eastern Ukraine located in an area with geologic and industrial sources of environmental mercury, and residents of Artemivsk, a nearby comparison city outside the mercury-enriched area. Samples of urine, blood, hair, and nails were collected from study participants, and a questionnaire was administered to obtain data on age, gender, occupational history, smoking, alcohol consumption, fish consumption, tattoos, dental amalgams, home heating system, education, source of drinking water, and family employment in mines. Median biomarker mercury concentrations in Artemivsk were 0.26 μg/g-Cr (urine), 0.92 μg/L (blood), 0.42 μg/g (hair), 0.11 μg/g (toenails), and 0.09 μg/g (fingernails); median concentrations in Horlivka were 0.15 μg/g-Cr (urine), 1.01 μg/L (blood), 0.14 μg/g (hair), 0.31 μg/g (toenails), and 0.31 μg/g (fingernails). Biomarkers of mercury exposure for study participants from Horlivka and Artemivsk are low in comparison with occupationally exposed workers at a mercury recycling facility in Horlivka and in comparison with exposures known to be associated with clinical effects. Blood and urinary mercury did not suggest a higher mercury exposure among Horlivka residents as compared with Artemivsk; however, three individuals living in the immediate vicinity of the mercury mines had elevated blood and urinary mercury, relative to overall results for either city. For a limited number of residents from Horlivka (N = 7) and Artemivsk (N = 4), environmental samples (vacuum cleaner dust, dust wipes, soil) were collected from their residences. Mercury concentrations in vacuum cleaner dust and soil were good predictors of blood and urinary mercury.     

Evaluation of biological impregnation of a population exposed to high concentration of arsenic in water supply, Ferrette, 1997]

BACKGROUND: The population of Ferrette has been exposed to well-water with arsenic (As) levels higher than legal threshold. The aim of this study was to assess the relationships between daily tap-water consumption, As quantities thus ingested and biological arsenical impregnation. METHODS: The study was carried out on a sample of 100 people in the town of Ferrette and 100 people in the town of Seppois-le-Bas where the water quality is satisfactory. Ingested water and As were assessed by the mean of a food questionnaire. The quantity of ingested As was related to the body weight and compared to the tolerable daily intake (TDI) of 2 micrograms/kg/d. Biological impregnation was assessed by measuring out As in hair sample. RESULTS: The daily ingested As intake of Ferrette population ranged from 0 to 32 micrograms/kg/d. One half of the population ingested more than 2 micrograms/kg/d. A quarter of the population ingested more than 4.3 micrograms/kg/d. 15% of Ferrette inhabitants yielded an As hair level higher than 0.1 ng/mg [IC95%: 8.7%-23.5%], versus 7% [IC95%: 2.9-13.9%] for the inhabitants of Seppois-le-Bas (p = 0.07). Among those who ingested an amount of As higher than the TDI, 19% were found to have detectable As hair levels, versus 9% for those who ingested less than the daily acceptable amount (p = 0.18). CONCLUSION: One half of the population of Ferrette absorbed an As amount double to the TDI, evidencing the reality of the exposure. We did not find any statistically significant relation between the ingested As amount and biological As impregnation nor between exposure to water containing excessive As level and As biological impregnation.