M. A. Bosque

Dietary intake of lead and cadmium from foods in Tarragona Province, Spain

For most people, the main route of exposure to heavy metals is through the diet. Lead and cadmium are ubiquitously distributed throughout the environment and it is unavoidable that traces of these metals can be detected in virtually all plant and animal organisms, and hence in our food. In previous studies, the average content of lead and cadmium in marine species and edible vegetables commonly consumed by the inhabitants of Tarragona was previously estimated. The purpose of the present work was to determine lead and cadmium content in common basic items of the major food groups, as well as to calculate the daily intake of lead and cadmium by the population from Tarragona.

CONCENTRATIONS OF LEAD AND CADMIUM IN EDIBLE VEGETABLES FROM TARRAGONA PROVINCE, SPAIN

The lead and cadmium content of 20 species of edible vegetable collected in Tarragona Province (Spain) was investigated. Samples consisting of bulbs, and leaves and soft stalks (chard, parsley, spinach and lettuce) contained the highest levels of both metals. In contrast, fruits and similar garden produce (tomato, green pepper, cucumber, artichoke, green bean and broad bean) contained the lowest concentrations of lead and cadmium in both the northern and southern area of the province. Most species analyzed did not show any significant differences between the two study areas. The mean daily intakes of lead and cadmium by man have been estimated to be: 47.5 micrograms Pb and 15.3 micrograms Cd (north), and 37.5 micrograms Pb and 32.5 micrograms Cd (south). These values do not pose a health risk for consumers, according to the levels proposed by FAO/WHO.

Embryotoxicity and teratogenicity of uranium in mice following subcutaneous administration of uranyl acetate

The effects of multiple maternal subcutaneous injections of uranyl acetate dihydrate (0.5, 1, and 2 mg/kg/d) from d 6 to d 15 of gestation were evaluated in Swiss mice. External, internal soft-tissue and skeletal examinations of fetuses were performed on gestation d 18. Maternal toxicity occurred in all uranium-treated groups as evidenced primarily by deaths as well as significant decreases in weight gain and in body weight at termination. Although it was not dose-related, embryotoxicity also occurred in all uranium-treated groups (significant increases in the number of nonviable implantations and in the percentage of postimplantation loss). Fetal body weight was significantly decreased at 1 and 2 mg/kg/d, whereas the number of total internal and total skeletal defects showed dose-dependent increases at 0.5, 1, and 2 mg/kg/d. Most morphological defects were developmental variations, whereas malformations were only detected at 1 and 2 mg/kg/d. On the basis of these data, both the maternal no-observable-adverse-effect level (NOAEL) and the NOAEL for embryotoxicity of uranyl acetate dihydrate were below 0.5 mg/kg/d, whereas the NOAEL for teratogenicity was 0.5 mg/kg/d.

Mercury concentrations in marine species from the coastal area of Tarragona Province, Spain. Dietary intake of mercury through fish and seafood consumption

A total of 592 samples of 21 species of fish, cephalopods, crustaceans and molluscs were analyzed for mercury concentrations between November 1992 and February 1993 at four sites on the Tarragona coast in Catalonia, Spain. The results of this study show that mercury discharges into the marine environment of Tarragona Province have increased the mercury content of marine organisms, with fish and crustaceans being the groups which accumulated the highest levels of this element. In a subsequent study, the individual dietary intake of mercury from fish and seafood consumption by the population of Tarragona Province was estimated to be 16 micrograms day-1. This intake of mercury would not signify a health hazard for consumers of fish and seafood from the Tarragona coastal waters.

Effectiveness of sodium 4,5-dihydroxybenzene-1,3-disulfonate (Tiron) in protecting against uranium-induced developmental toxicity in mice

The effect of Tiron (sodium 4,5-dihydroxybenzene-1,3-disulfonate), a chelating agent used in the treatment of experimental poisoning by a number of heavy metals, on uranium-induced developmental toxicity was evaluated in Swiss mice. A series of four Tiron injections was administered intraperitoneally to pregnant mice immediately after a single subcutaneous injection of 4 mg/kg of uranyl acetate dihydrate given on day 10 of gestation and at 24, 48, and 72 h thereafter. Controls received 0.9% saline with or without uranyl acetate. Tiron effectiveness was assessed at 500, 1000 and 1500 mg/kg per day. Amelioration by Tiron of uranium-induced embryolethality was not noted at the two lower doses. The percentage of dead and resorbed fetuses in the Tiron-treated groups was not statistically different from that in the positive control group. However, treatment at 1500 mg/kg per day showed isolated protective effects against uranium fetotoxicity, such as that evidenced by the lack of differences in fetal body weight between this group and the uranium-untreated group, as well as by a decrease in the number of skeletal defects. According to these results, the ability of Tiron to protect the developing mouse fetus against uranium-induced developmental toxicity offers only modest encouragement with regard to its possible therapeutic potential for pregnant women exposed to this metal.

Lead and Cadmium Concentrations in Marine Organisms from the Tarragona Coastal Waters, Spain

Lead and cadmium are now recognized to be two of most important heavy metal contaminants of the marine environment. The Tarragona coastal area (Catalonia, NE Spain) is a biologically productive and physically diverse marine ecosystem, with a very important commercial fishing industry. Two rivers, the Ebro (South) and the Francoli (North) flow into the Mediterranean Sea at the Tarragona coastal waters, which are subjected to large loads of toxic industrial residues (including heavy metals). Although considerable data have been accumulated on the distribution and levels of heavy metals in marine species from different areas of the Mediterranean Sea, data from the Taragona coastal area are not available in the literature. The purpose of the present study was to determine the distribution and concentrations of lead and cadmium in the marine species commonly consumed by the population of Tarragona, as well as to learn whether these levels may constitute a health hazard for the consumers. Lead and cadmium were measured in 23 commercially significant marine species from the Tarragona coastal waters.

Heavy metals in marine species from the Tarragona Coast, Spain

Abstract The edible parts of several species of fish, mollusks and crustaceans from the Tarragona Coast (Spain) were analyzed for vanadium, manganese, chromium, zinc and cobalt. The nineteen marine species sampled are commercially important and may be useful to assess the uptake of toxic metals in a Mediterranean area particularly exposed to polluting inputs from the Ebro and Francoli rivers. The related levels ranged from less than 0.001 to 0.259 μg/g for vanadium; from 0.113 to 1.727 μg/g for manganese; from less than 0.0006 to 0.469 μg/g for chromium; from 3.35 to 29.79 μg/g for zinc; and from less than 0.0004 to 0.304 μg/g for cobalt. These concentrations were similar or even lower than previously reported data in other latitudes. These levels of vanadium, manganese, chromium, zinc and cobalt in the marine species of the Tarragona coast do not pose a health hazard for consumers.

Cadmium in hair of school children living in Tarragona Province, Spain. Relationship to age, sex, and environmental factors.

Cadmium concentrations were determined in the hair of 226 school children in an industrial and in a rural area of Tarragona Province (NE Spain). The influence of sex, age, hair color, smoking habits of the household members, and parents’ occupation on the children’s hair cadmium levels was also evaluated. Children living in the industrial area had much more cadmium in their hair than those living in the rural area (median: 0.327 vs 0.002; arithmetic mean: 0.401 vs 0.119 μg/g). Girls had more cadmium in their hair than boys, and cadmium levels decreased with the age independently of the sex. Smoking habits and parents’ occupation also influenced the hair cadmium content in the children examined. In contrast, hair color has no influence on hair cadmium values.

meso-2,3-Dimercaptosuccinic acid and prevention of arsenite embryotoxicity and teratogenicity in the mouse

meso-2,3-Dimercaptosuccinic acid (DMSA), an antidote for the treatment of experimental and human poisoning by a number of heavy metals, has been reported to reduce the lethality of animals poisoned with arsenic more effectively than 2,3-dimercaptopropanol. In the present study, the effect of DMSA on arsenite-induced embryotoxic and teratogenic effects was evaluated in mice. In a first experiment, a series of four DMSA injections was administered sc to pregnant Swiss mice immediately after a single ip injection of 12 mg/kg of sodium arsenite (NaAsO2) given on Day 10 of gestation, and at 24, 48, and 72 hr thereafter. DMSA effectiveness was assessed at dosage levels of 0, 80, 160, and 320 mg/kg/day. Treatment with DMSA significantly reduced the embryolethality and the incidence of gross external and skeletal malformations and variations provoked by NaAsO2. Based on these findings, the effect of increasing the time interval between acute arsenite exposure and initiation of DMSA therapy was investigated in a second experiment. On Day 10 of gestation, DMSA (320 mg/kg) was administered sc to pregnant mice at 0, 0.25, 0.50, 1, 4, or 12 hr after a 12-mg/kg ip dose of NaAsO2. Embryotoxicity and teratogenicity derived from NaAsO2 exposure were significantly reduced when DMSA was given during the first hour after NaAsO2 injection. According to these results, a delay between acute arsenite intoxication and DMSA treatment should be avoided to have a practical beneficial effect on the arsenite exposed conceptus.

Evaluation of the developmental toxicity of 2,3-dimercapto-1-propanesulfonate (DMPS) in mice. Effect on mineral metabolism

The sodium salt of 2,3-dimercapto-1-propanesulfonic acid (DMPS), a potent chelating agent used in the treatment of inorganic and organic heavy metal intoxications was evaluated for developmental toxicity in pregnant Swiss mice. DMPS was administered by gavage at doses of 0, 75, 150 and 300 mg/kg per day on gestational days 6-15. Females were evaluated for body weight gain, food consumption, appearance and behavior, survival rates and reproduction data. Cesarean sections were performed on gestation day 18. There were no maternal toxic effects, and no treatment-related changes were recorded in the number of total implants, resorption, the number of live and dead fetuses, fetal body weight or fetal sex distribution data. Gross external, soft tissue and skeletal examination of the DMPS-treated fetuses did not show significant differences at any dose in comparison with the controls. Mineral analysis of maternal and fetal tissues revealed slight effects of DMPS on metabolism of calcium, magnesium, zinc, copper and iron. The results of this study in mice indicate that DMPS is not a developmental toxicant at levels up to 300 mg/kg per day.