Internal exposure to organic substances in a municipal waste incinerator

Summary Fifty-three persons occupied in a municipal waste incinerator were examined with respect to their internal exposure to organic substances which may be produced during pyrolysis of organic matter. For this purpose the levels of benzene in blood, polychlorinated biphenyls (PCBs) and hexachlorobenzene (HCB) in plasma, and mono- (MCPs), di- (DCPs), tri- (TCPs), tetra-(TECPs) and pentachlorophenol (PCP) and hydroxypyrene in urine were determined. For control purposes, 431 men and women were examined. Significantly higher values for the workers were found for the excretion of hydroxypyrene [median (m): 0.24vs 0.11 g/l; non-smokers], 2,4/2,5-DCP (m: 10.5 vs 3.9 g/l) and 2,4,5-TCP (m: 1.2 vs 0.8 g/l) and for the HCB level in plasma (m: 4.4 vs 2.8 g/l). For the concentrations of 4-MCP and 2,3,4,6/2,3,5,6-TECP, the controls had significantly higher concentrations in urine than did the workers in the incineration plant (m: 4-MCP 1.7 vs 1.2; 2,3,4,6/2,3,5,6-TECP: 1.2 vs 0.3 g/l). No significant differences between workers and controls were detected with respect to benzene in blood (m: 0.20 vs 0.28 g/l; non-smokers), 2,4,6-TCP and PCPs in urine (m: 0.85 vs 0.60 and 2.2 vs 2.2 g/l) or the levels of PCB congeners in plasma (m: 138, 153, 180: 5.6 vs 4.1 g/l). The elevated levels of hydroxypyrene, 2,4/2,5-DCP, 2,4,5-TCP and HCB in biological material may be related to the incineration of the waste. These elevations, however, are very small and are of interest more from the environmental than from the occupational point of view.     

Toxicity of aldicarb and fonofos to the early-life-stage of the fathead minnow

Flow-through early-life-stage (ELS) toxicity tests were conducted with the pesticides aldicarb (Temik^®) and fonofos (Dyfonate^®) to determine their effect on the survival and growth of fathead minnows. Concentrations of 78g/L of aldicarb and 16g/L of fonofos did not affect survival and growth. However, 156g/L of aldicarb and 33g/L of fonofos were lethal to larval-juvenile exposed for 30 days post-hatch. The maximum acceptable toxicant concentration (MATC) of aldicarb and fonofos for the fathead minnow is estimated to be between 78–156g/L and 16–33g/L, respectively. The corresponding chronic values (geometric mean of MATC values) would be 110g/L and 23g/L. Acute toxicity tests gave 96-hr LC50 values of 1370g aldicarb/L and 1090g fonofos/L. The acute-chronic ratio (96-hr LC50/chronic value) is 12 for aldicarb and 47 for fonofos.     

Blood styrene concentrations in a “normal” population and in exposed workers 16 hours after the end of the workshift

Summary Blood styrene was measured by a gas chromatography-mass spectrometry method in 81 normal people and in 76 workers exposed to styrene. In the normal subjects, styrene was also tested in alveolar and environmental air. Styrene was found in nearly all (95%) blood samples. Average styrene levels in the normal subjects were 221 ng/1 in blood (Cb), 3 ng/1 in alveolar air (Ca) and 6 ng/1 in environmental air (Ci). Styrene levels did not differ significantly between smokers and non-smokers, 95% of values being below 512 ng/1 in Cb, 7 ng/1 in Ca and 15 ng/l in Ci. In workers with an average exposure to styrene of 204 g/l, at the end of the workshift, mean blood styrene concentration was 1211 g/l. In blood samples collected at the end of the Thursday shift, styrene levels were significantly higher (1590 g/1) than those found at the end of the Monday shift (1068 g/l. A similar difference was found in samples taken the morning after exposure (60 and 119 g/l, respectively). Significant correlations between blood and environmental styrene were found both at the end of the shift and the morning after exposure (r=0.61 and 0.41, respectively). In workers occupationally exposed to styrene, 16 h after the end of the workshift, blood styrene (94 g/l) was significantly higher than that found in the normal subjects (0.22 g/l). The half-life of blood styrene was 3.9 h.     

Effects of tributyltin on survival,growth, morphometry,and RNA-DNA ratio of larval striped bass,Morone saxatilis

Effects of tributyltin (TBT) on survival, growth, morphometry, and RNA-DNA ratio in larval striped bass(Morone saxatilis) were assessed in three experiments. In Experiment I, 13 day old larvae were exposed to 0, 0.067, 0.766, or 2.284 g TBT/L for 6 days. All larvae exposed to 2.284 /L died by day 5; exposure to 0.766 g/L significantly reduced survival relative to controls (59.8% vs. 81.8%). Significant, concentration-dependent decreases in body depth occurred in larvae exposed to 0.067 and 0.766 g/L. In Experiment II, all 16 day old larvae exposed to 1.498 g/L died by day 6. Survival, weight, and morphometry parameters were not significantly different in larvae exposed to 0, 0.052, or 0.444 g/L for 7 days. In Experiment III, survival was similar in 21 day old larvae exposed to 0, 0.055, 0.218, or 0.514 /L for 7 days. Notochord length and dry weight decreased significantly in larvae exposed to 0.514 g/L. Weight and morphometry parameters were more sensitive indicators of sublethal stress than RNA-DNA ratio. Maximum TBT concentrations reported in Chesapeake Bay marinas are likely to cause increased larval mortality. Longer-term studies are needed to assess effects at <0.050 g/L, which may be more representative of habitat conditions.     

Internal lead and cadmium exposure in 6-year-old children from western and eastern Germany

Lead and cadmium levels in blood and deciduous teeth (shed incisors only) of 6-year-old German children were determined in 1991 in a large epidemiological study carried out in rural and urban areas of western Germany (Duisburg, Essen, Gelsenkirchen, Dortmund, Borken) and eastern Germany (Leipzig, Halle, Magdeburg, Osterburg, Gardelegen, Salzwedel). In total, blood lead and cadmium levels of 2311 German children and tooth lead and cadmium levels of 790 German children were analyzed. Blood lead levels were generally low in all study areas with geometric means between 39.3 g/1 and 50.8 g/l in the western German and between 42.3 g/1 and 68.1 g/l in the eastern German study areas. The mean blood lead level of Turkish children (n = 213) living in the western German study areas was 50.1 g/l and thus 5.6 g/1 higher than the overall geometric mean of the western German children. The higher exposure may be explained by a higher oral uptake from food and different living conditions. These children were excluded from multiple regression analysis because they were all living in the western study areas. The mean tooth lead levels ranged between 1.50 and 1.74 g/g in the western and between 1.51 g/g and 2.72 g/g in the eastern study areas. Thus, they show a distribution pattern similar to blood. Blood and tooth lead levels were higher in urban than in rural areas and higher in the eastern German than in the western German study areas. With regard to the blood and tooth cadmium concentrations, no significant differences between the study areas could be found. The mean cadmium levels in blood ranged between 0.12 g/1 and 0.14 g/l and the mean tooth cadmium concentrations between 20.8 ng/g and 27.8 ng/g. Blood and tooth lead and cadmium levels of the eastern and western German children were thus mainly at a relatively low level in all rural and urban study areas. The study demonstrates and confirms that blood and tooth lead levels are influenced by several demographic, social, and environmental variables. The results indicate that there has been a further significant decrease of lead and cadmium exposure in western German children since our last epidemiological study carried out in the same study areas in 1985/1986.     

Effect of aflatoxin B and rubratoxin B on bacteriophage and rabbit cornea cells

Summary Rabbit cornea cells exhibited a sensitivity to 1 g aflatoxin b₁ and 5 g rubratoxin B per ml of growth medium. No changes were observed in the bacteriophages tested in the presence of 25 g aflatoxin b₁ or 100 g rubratoxin B per ml of medium by the plaque-forming unit method or single-step growth curves.     

Nitrous oxide in blood and urine of operating theatre personnel and the general population

Nitrous oxide (N₂O) was assayed in 676 urine samples and 101 blood samples provided after exposure by operating theatre personnel from nine hospitals. The blood and urine assays were repeated in 25 subjects 18 h after the end of exposure. For 80 subjects, environmental N₂O was also measured during intraoperative exposure. Mean urinary N₂O in the 676 subjects at the end of exposure was 40 g/l (range 1–3805 g/l); in 10 of the 676 subjects, urinary N₂O was in the range 279–3805 g/l (mean 1202 /l). The 98^th percentile was 120 g/l. Mean blood N₂O at the end of exposure, measured in 101 subjects, was 21 g/l (median 16 g/l, range 1–75 g/l). Blood and urine N₂O (1.5 g/l and 4.9 g/l, respectively) in 25 subjects, 18 h after exposure, was significantly higher than in occupationally non-exposed subjects (blood 0.91 g/l, urine 1 g/l). Environmental exposure was significantly related to blood and urinary N₂O (r = 0.59 andr = 0.64, respectively). Blood and urinary N₂O were significantly related to each other (r = 0.71), and were equivalent to about 25% of the environmental exposure level. The mean urinary N₂O of 1202 g/l in 10/676 subjects was not related to environmental exposure in the operating theatre. The highest urinary N₂O levels measured in these 10/676 subjects could be explained by an asymptomatic urinary infection.     

Contaminant levels in harbor seals from the northeastern United States

The concentrations of polychlorinated biphenyls (PCBs), organochlorine pesticides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzofurans (PCDF), polychlorinated dibenzo-p-dioxins (PCDD), and mercury (Hg) were determined in blubber and liver tissues of harbor seals (Phoca vitulina) collected along the northeast coast of the U.S. Average PCB concentrations in seal blubber (sum of congeners) were 12.0 g/g (wet weight) with a range of 7.30 to 24.3 g/g in 1980 and 6.66 g/g (wet weight) with a range of 2.61 to 11.3 g/g in 1990–1992. Comparisons between blubber data from this study and previous work indicated that the concentration of PCBs along the northeast coast of the U.S. may have decreased over the past twenty years.The average p,p-DDE concentrations in seal blubber were 10.9 g/g (wet weight) in 1980 with a range of 6.95 to 21.9 g/g and 4.12 g/g (wet weight) with a range of 1.83 to 7.84 g/g in 1990–1992. Only trace amounts of PCDFs and PCDDs were found in a few blubber samples; levels in most tissues were below detection (3–5 pg/g) (wet weight). Trace amounts (<30 ng/g) of phenanthracene, anthracene, and alkylated MW-178 compounds were found in some seal samples; all other PAH compounds were below the detection level (5–15 ng/g).Toxic equivalents (TEQ) of selected coplanar and mono-ortho PCB congeners and relative toxic equivalents (RTE) (pg total TEQ/g total PCB) were calculated, using recently proposed dioxin toxic equivalent factors (Ahlborg et al. 1994). The TEQs ranged from 41 to 315, and the RTEs ranged from 2.25 to 16.3. The RTEs for seal blubber indicated that the present values were in the midrange of those reported in the literature. Toxic equivalents calculated on the basis of the concentrations of the coplanar PCBs, PCDDs, and PCDFs indicated that coplanar PCBs, rather than PCDDs and PCDFs, may pose a more important toxic threat to harbor seals.Mercury levels in liver tissue averaged 70.0 g/g (wet weight) and 44.1 g/g (wet weight) in the 1991 and 1980 samples, respectively, and are similar to those found in relatively polluted waters of the British Isles.     

Accumulation of Selenium and Lack of Severe Effects on Productivity of American Dippers (Cinclus mexicanus) and Spotted Sandpipers (Actitis macularia)

Selenium has been found at elevated concentrations in water, sediments, and aquatic biota in the Elk River (British Columbia, Canada) and some of its tributaries downstream of several coal mines. Selenium water concentrations in those areas exceed Canadian and British Columbia guidelines and are above levels at which adverse effects to fish and waterfowl could occur. We compared selenium concentrations in the eggs of two riverine waterbirds, American dippers and spotted sandpipers, with measures of productivity: the number of eggs laid, egg hatchability, and nestling survival. In American dippers, the mean egg selenium concentration from the exposed areas, 1.10±SE 0.059 g/g wet weight, was indistinguishable from the reference areas, 0.96±SE 0.059 g/g wet weight. For spotted sandpipers, the mean egg selenium concentration in the exposed areas, 2.2±0.5 g/g wet weight, was significantly higher than in the reference areas, 1.2±0.14 g/g wet weight, but less than reported thresholds for waterfowl and other shorebirds. There were no significant differences in egg hatchability between dippers in reference and exposed areas, but reduced hatchability was apparent for sandpipers in exposed locations. Despite the slightly reduced hatchability in sandpipers, overall productivity was higher than regional norms for both species; thus, selenium did not affect the number of young recruited to local populations. We did not observe teratogenic effects in either species, although none was expected at these concentrations. Despite moderately high selenium concentrations in the water, mean egg selenium concentrations were less than predicted from uptake models. We hypothesise that the relatively low uptake of selenium into the eggs of the two waterbirds in this study is likely due to their lotic environments low biological transformation and uptake rates.     

Chronic toxicity and bioaccumulation of 2,5,2′,5′- and 3,4,3′,4′-tetrachlorobiphenyl and Aroclor® 1242 in the amphipodHyalella azteca

The addition of 100 (g/L of Aroclor^® 1242 (A1242) or 2,5,2,5-tetrachlorobiphenyl (TeCB) during 10 week chronic toxicity tests withHyalella azteca resulted in complete mortality. There were no effects on survival, growth, or reproduction after addition of 30 g/L. Toxic effects were observed at tissue levels of between 30 and 180 g/g on a wet weight basis, and tissue levels appear to be a better indicator of toxicity than levels in water. No toxic effects were observed after additions of up to 2,700 g/L of the coplanar congener 3,4,3,4-TeCB.H. azteca has the ability to avoid accumulating in excess of 140 g/g 3,4,3,4-TeCB. The amount taken up was proportional to the amount added in water up to 100 g/L, but was constant at higher additions, possibly accounting for its relatively low toxicity. The low toxicity of the coplanar congener, as compared to the non-coplanar 2,5,2,5-TeCB, is in direct contrast to the high toxicity of coplanar PCB congeners to mammals and may be associated with slower rates of aromatic hydrocarbon metabolism in amphipods. Polychlorinated biphenyl levels measured in amphipods from Lake Ontario are approximately 100-fold below levels associated with toxicity inH. azteca, but are above levels which, through biomagnification up the food chain, lead to salmonid residues in excess of 2 g/g, a tolerance limit for human consumption.     

Search for anti-laminin antibodies in the serum of workers exposed to cadmium,mercury vapour or lead

Summary Anti-laminin antibodies were sought for in the serum of workers exposed to mercury vapour (Hg, n = 58), lead (Pb, n = 38) or cadmium (Cd, n = 47). Thirty-one workers removed from Cd exposure for an average of eight years were also examined. Compared with control workers matched for age and socio-economic status, the prevalence of circulating anti-laminin antibodies was not increased in workers exposed to Hg (mean duration of exposure: 7.9 years and mean urinary excretion of Hg: 72 g/g creatinine) nor in those exposed to Pb (mean duration of exposure: 10.6 years and mean Pb levels in blood: 535 g/l). In contrast, anti-laminin antibodies were significantly more prevalent in Cd-exposed workers whose urinary Cd exceeded 20 g/g creatinine. This observation was made in both currently exposed workers and in workers removed from Cd exposure (mean duration of exposure: 9.4 and 24.6 years and mean urinary Cd: 7.8 and 13.4 g/g creatinine respectively). These autoantibodies were found in Cd workers with normal renal function as well as in those with increased proteinuria.     

Behavioral effects of waterborne carbofuran in goldfish

The effects of concentration (1, 10, 100 g/L) and duration (4, 8, 12 h) of exposure to carbofuran were assessed on the swimming activity, social interactions, and behavioral responses of goldfish to a flow (0.1 L/min) of water, with or without chironomids. Observations were also made on the behavioral responses of unexposed goldfish to a flow (0.1 L/min) of carbofuran-contaminated water. A 4-h exposure of goldfish 1 g/L carbofuran produced a significant increase in sheltering, burst swimming, and nipping. Responses were enhanced at 100 g/L. After a 12-h exposure, the behavioral effects of 1 g/L carbofuran were less apparent. However, burst swimming at 10 g/L, and sheltering, nipping and burst swimming at 100 g/L, were still significantly increased after a 12-h exposure to carbofuran. Grouping was not consistently affected by exposure conditions. Chemical attraction to a filtrate of chironomids was significantly reduced after the 4-h exposure to 1 g/L carbofuran. Decreased attraction to the food extract was less apparent after the 12-h exposure, except at 100 g/L carbofuran. A significant decrease in attraction to a flow of uncontaminated water was also observed after a 4-h exposure to 10 and 100 g/L carbofuran. Unexposed goldfish did not show avoidance reaction to a flow of carbofuran-contaminated water, even at a concentration (10 mg/L) exceeding the mean 96-h LC-50 in cyprinids (0.5–1 mg/L). However, at all concentrations tested (0.1, 1, 10 mg/L), goldfish quickly reacted to the introduction of the solution of carbofuran by increased burst swimming and nipping. These results are discussed in the light of the data concerning behavioral and neurotoxic effects of carbamate and organophosphorous insecticides in fish.     

Blood toluene as a biological index of environmental toluene exposure in the “normal” population and in occupationally exposed workers immediately after exposure and 16 hours later

Blood toluene was measured in a group of 100 workers occupationally exposed to a mean 8-h environmental toluene concentration of 128 g/l (34 ppm), and in a group of 269 normal subjects without occupational exposure to toluene. The mean blood toluene of the workers at the end of the shift and the following morning, after 16 h, was 457 and 38 g/l, respectively. The normal subjects had a blood toluene level of 1.1 g/l. On the basis of the highly significant correlation between blood toluene and occupational exposure, it can be calculated that environmental toluene exposure of 188 and 377 g/l (50 and 100 ppm) gives end-of-shift blood toluene levels of 690 and 1390 g/l, respectively. The corresponding blood toluene levels on the following morning are 50 and 100 /l, respectively.     

Biological monitoring of isocyanates and related amines

Summary Five men were exposed to toluene diisocyanate (TDI) atmospheres for 7.5 h. The TDI atmospheres were generated by a gas-phase permeation method, and the exposures were performed in an 8-m3 stainless-steel test chamber. The mean air concentration of TDI was ca. 40 g/m³, which corresponds to the threshold limit value (TLV) of Sweden. The inhaled doses of 2,4- and 2,6-TDI were ca. 120 g. TDI in the test chamber air was determined by an HPLC method using the 9-(N-methyl-aminomethyl)-anthracene reagent and by a continuous-monitoring filter-tape instrument. After hydrolysis of plasma and urine, the related amines, 2,4- and 2,6-toluenediamine 2,4-, and 2,6-TDA), were determined as pentafluoropropionic anhydride (PFPA) derivatives by capillary gas-chromatography using selected ion monitoring (SIM) in the electron-impact mode. The urinary elimination of the TDAs showed a possible biphasic pattern, with rapid first phases for 2,4-TDA (mean t _1/2 for the concentration in urine, 1.9 h) and for 2,6-TDA (mean t _1/2 for the concentration in urine, 1.6 h). The cumulative amount of 2,4-TDA excreted in urine within 28 h ranged from 8% to 14% of the estimated dose of 2,4-TDI, and the cumulative amount of 2,6-TDA in urine ranged from 14% to 18% of the 2,6-TDI dose. The average urinary level of 2,4-TDA was 5 g/l in the 6 to 8-h sample (range 2.8–9.6 g/l), and the corresponding value for 2,6-TDA was 8.6 g/l (range, 5.6–16.6 g/l). Biological monitoring of exposure to 2,4- and 2,6-TDI by analysis of 2,4- and 2,6-TDA in urine is feasible.     

DDT Residues in samples of human milk,and in mothers' and cord blood serum,in a continental town in Croatia (Yugoslavia)*

Summary Concentrations of p,p'-DDE, p,p-DDD, and p,p-DDT were determined in 34 samples of human milk obtained 3–5 days after delivery and in 37 samples obtained at later times of lactation (up to 55 weeks). All samples contained p,p-DDE, but only several contained p,p-DDD and p,p-DDT. The concentrations of p,p-DDE were 31 g/l in the beginning of lactation and 53 g/l at later time intervals. The concentration ranges in both groups overlap almost completely and the difference in the mean values is not significant.Serum samples from 35 mothers and cord blood were also analyzed. All samples contained p,p-DDE, the concentrations being 18 g/l and 6.8 g/l in the mothers' and cord blood serum, respectively. Serum samples of 24 nonpregnant women contained the same amount of p,p-DDE (20 pg/1) as mothers' sera.All samples were collected in a continental town of Croatia (Yugoslavia) between 1977 and 1979. The concentrations of DDT residues were determined by gas chromatography, and two methods for extraction from milk were used and compared.This work was supported in part by the Environmental Protection Agency (USA) and the World Health Organization (Geneva)     

Isomer-specific analysis and toxic evaluation of polychlorinated biphenyls in striped dolphins affected by an epizootic in the western Mediterranean sea

Isomer-specific concentrations of polychlorinated biphenyls (PCBs) including planar, mono- and di-ortho congeners and concentrations of DDT were determined in striped dolphins affected by a morbillivirus epizootic in the western Mediterranean in 1990. Extremely high concentrations of PCBs ranging from 94 to 670 g/g (wet wt) were detected in the blubber. Similarly, DDT concentrations were high, between 22 and 230 g/g (wet wt). The concentrations of three non-ortho coplanar PCBs were 43 (3,3,4,4-T₄CB), 6.8 (3,3,4,4,5-P₅CB), and 7.8 (3,3,4,4,5,5-H₆CB) ng/g (wet wt), respectively, the highest residue levels reported to date. The estimated 2,3,7,8-TCDD toxic equivalents of non-, mono- and di-ortho PCB congeners in striped dolphins were several times higher than those observed for other marine mammals and humans. Mono-ortho congeners contributed greater 2,3,7,8-TCDD toxic equivalents than non-ortho members. The higher ratio of 3,3,4,4,5,5-H₆CB/3,3,4,4,5-P₅CB (IUPAC 169/126) suggested a strong induction of mixed function oxidase enzymes and highlighted the possibility of using this ratio as an index for risk assessment of PCB contamination in marine mammals. Elevated concentrations of PCBs may have played a role in the immune depression in striped dolphins, ultimately leading to the development of morbillivirus disease.     

Blood lead in the general population in Poland

Lead concentration in venous blood (Pb-B) was investigated in 1122 inhabitants (including 555 children under 10 years of age) of five Polish towns with no large industrial lead emitters (group I) and in 1246 persons (707 children under 10 years of age) living in the vicinity of zinc and copper mills (group II). The samples were analysed using electrothermal atomic absorption spectrometry (ETAAS) and the performing laboratory participated in the external quality control scheme during the study period (1992–1994). In group I the mean geometric Pb-B concentrations ranged from 23.8 to 48.3g/l in females, from 42.5 to 76.8 g/l in males and from 29.9 to 62.5 g/l in children. In group II, the mean geometric Pb-B concentrations were significantly higher and ranged from 49.4 to 105 g/l in females, from 98.5 to 149 g/l in males and from 73.7 to 114 g/l in children, the values decreasing as the distance from the source of emission increased. Cigarette smoking was found to bring about a significant increase in Pb-B levels for both males and females. A significant correlation was noted between Pb-B concentrations in mothers and children. The ratio between child and maternal Pb-B concentrations amounted to approximately 1.0 for group I and to about 0.5 for group II. These findings indicate the necessity of undertaking preventive activities over the lead-contaminated areas. However, the lead hazard in Poland seems to be associated with point sources of emission and hence does not concern the whole population.     

Exposure to lead of the Belgian population

Summary According to the Council Directive of 29 March 1977 on biological screening of the population for lead, the blood-lead levels (PbB) were determined in samples of the Belgian population not occupationally exposed to this metal. Two campaigns of sampling were performed: the first one in 1979 (1678 samples analysed) and the second in 1981 (1000 samples analysed). Sampling was done in urban and industrial zones, as well as in areas where lead risk could be present. Concerning the urban and industrial areas, the results obtained seem to indicate that a particular lead risk does not exist for the adult population if we consider the reference levels of the CEE Directive. Moreover, the results of the second campaign of sampling showed a decreasing trend: the median PbB values dropped from 183 to 156 g/l in Brussels and from 192 to 139 g/l in Liège. This could be partly due to the limitation of the lead content of gazoline. On the other hand, the results of the surveys clearly demonstrated the existence of two areas where an obvious lead risk exists. In one of those, the lead risk is of industrial origin (lead smelter) and concerns mainly children: median PbB value 260 g/l, percentile 90 and 98 respectively 390 and 430 g/l. In the other one, the lead risk is from a hydric source and concerns adults and children: median PbB value 258 g/l, percentile 90 and 98 respectively 370 and 520 g/l.     

Sublethal Effects of Trace Metals (Cd,Cr, Cu,Hg) on Embryogenesis and Larval Settlement of the Ascidian <Emphasis Type="Italic">Ciona intestinalis</Emphasis>

Toxicity of Cadmium (Cd), Chromium (Cr), Copper (Cu), and Mercury (Hg) on the early developmental stages of Ciona intestinalis was investigated. Developmental defects of larvae after exposure of gametes throughout their development to the larval stage were assessed. Gamete exposure to increasing metal concentrations resulted in a significant decrease of the percentage of normally hatched larvae, showing median effective concentrations (EC₅₀) of 721 g/L (6.42 M) for Cd, 12772 g/L (226 M) for Cr, 36.6 g/L (0.576 M) for Cu, and 44.7 g/L (0.223 M) for Hg. Larval attachment was significantly affected when gametes were exposed to the metals throughout development. The EC₅₀ reducing larval attachment by 50% were 752 g/L (6.7 M) for Cd, 15026 g/L (289 M) for Cr, 67.8 g/L (1.607 M) for Cu, and 78.1 g/L (0.389 M) for Hg. Therefore, on a molar basis Hg is three times more toxic than Cu, 20–30 times more than Cd, and 700–1000 times more toxic than Cr, for both responses.     

Aluminiumspiegel im Blutplasma bei Arbeitern in der Aluminium-Industrie

Zusammenfassung Bei Arbeitern in der Produktion von Aluminiummetall wurden die Aluminiumgehalte im Blutplasma bestimmt. Bei Arbeitern in der Elektrolyse wurden Gehalte von 5 bis 15g/l erhalten, während sie in der Giesserei bei etwa 5g/l lagen. Bei der nicht beruflich exponierten gesunden Kontrollbevölkerung betragen die Normalwerte höchstens 1 bis 3g/l. Wesentlich höhere Gehalte, nämlich im Bereiche von 100 bis 500g/l, wurden bei Patienten mit chronischem Nierenversagen ermittelt, da diese täglich einige Gramm Aluminium-hydroxid zur Phosphatbindung aufnehmen müssen und in den regelmässigen Dialysesitzungen nur ein Teil des aufgenommenen Aluminiums wieder eliminiert werden kann. Bei solch hohen Gehalten können gelegentlich zentralnervöse Störungen, wohl verursacht durch Aluminiumverbindungen, auftreten. Es bestehen keine Hinweise dafür, dass die Belastung der Arbeiter in einer Aluminiumhütte irgendwelche Gesundheitsbeeinträchtigungen haben könnte

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Aluminium blood levels in aluminium workers

Summary Aluminium levels in the blood plasma were determined in a group of workers in an aluminium plant. The aluminium concentration in the plasma of potroom workers was 5 to 15g/l whereas workers in the cast-house showed values of approximately 5g/l. In a healthy non-occupationally exposed control population, normal values of less than 1 to 3g/l were obtained. Considerably higher values, in the range of 100 to 500g/l, were found in kidney patients, since they must ingest several grams of aluminium-hydroxides daily to bind phosphates in the intestinal system. The aluminium is, however, only partially removed by dialysis. Occasionally central nervous disturbances, possibly due to aluminium, occur in these patients. However, there is no evidence of any health effects due to the intake of aluminium compounds in workers in the aluminium industry.

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Taux d'aluminium dans le sang d'ouvriers travaillant dans l'industrie d'aluminium

Resumé Les taux d'aluminium ont été détérminés dans le plasma sanguin d'ouvriers travaillant dans la production d'aluminium métallique. Chez les ouvriers travaillant dans l'électrolyse, des taux de 5 à 15g/l ont été trouvés, tandis que chez ceux travaillant dans la fonderie, ils se situent aux environs de 5g/l. Les valeurs normales d'une population professionnellement non exposée et de bonne santé se trouvent au maximum entre 1 et 3g/l. Des taux bien plus élevés entre 100 et 500g/l sont trouvés chez des patients souffrant d'insuffisance rénale chronique. Ces patients doivent absorber journellement plusieurs grammes d'hydroxide d'aluminium pour la fixation des phosphates. Cet aluminium ne peut être éliminé que partiellement lors des séances régulières de dialyse. En présence de concentrations aussi élevées, ont peut parfois trouver des dérangements du système nerveux central, probablement dûs aux composants d'aluminium. Il n'existe cependant aucun indice que l'exposition dans une usine de production d'aluminium n'affecte la santé des ouvriers.