Essentiality Toxicity Carcinogenicity Lead(Pb) Exposure Toxicokinetics Toxicity Neurologic, Neurobehavioral, and Developmental Effects in Children Mechanisms of Effects on the Developing Nervous System Peripheral Neuropathy Hematologic Effects Renal Toxicity Lead and Gout Effects on Cardiovascular System Immunotoxicity Bone Effects Reproductive Effects Birth Outcomes Carcinogenicity Other Effects Dose Response Treatment Organic Lead Compounds Mercury (Hg) Exposure Disposition and Toxicokinetics Metabolic Transformation Cellular Metabolism Toxicology Biological Indicators Treatment Nickel (Ni) Exposure Toxicokinetics Essentiality Toxicity Nickel Carbonyl Poisoning Dermatitis Indicators of Nickel Toxicity

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Toxic effects of metals

https://stacks.cdc.gov/view/cdc/37676/cdc_37676_DS1.pdf

Toxicological Profile for Lead

In 1992 Carlsen et al. reported a significant global decline in sperm density between 1938 and 1990 [Evidence for Decreasing Quality of Semen during Last 50 Years. Br Med J 305:609-613 (1992)]. We subsequently published a reanalysis of the studies included by Carlsen et al. [Swan et al. Have Sperm Densities Declined? A Reanalysis of Global Trend Data. Environ Health Perspect 105:1228-1232 (1997)]. In that analysis we found significant declines in sperm density in the United States and Europe/Australia after controlling for abstinence time, age, percent of men with proven fertility, and specimen collection method. The declines in sperm density in the United States (approximately 1.5%/year) and Europe/Australia (approximately 3%/year) were somewhat greater than the average decline reported by Carlsen et al. (approximately 1%/year). However, we found no decline in sperm density in non-Western countries, for which data were very limited. In the current study, we used similar methods to analyze an expanded set of studies. We added 47 English language studies published in 1934-1996 to those we had analyzed previously. The average decline in sperm count was virtually unchanged from that reported previously by Carlsen et al. (slope = -0.94 vs. -0.93). The slopes in the three geographic groupings were also similar to those we reported earlier. In North America, the slope was somewhat less than the slope we had found for the United States (slope = -0.80; 95% confidence interval (CI), -1.37--0.24). Similarly, the decline in Europe (slope = -2.35; CI, -3.66--1.05) was somewhat less than reported previously. As before, studies from other countries showed no trend (slope = -0.21; CI, -2.30-1.88). These results are consistent with those of Carlsen et al. and our previous results, suggesting that the reported trends are not dependent on the particular studies included by Carlsen et al. and that the observed trends previously reported for 1938-1990 are also seen in data from 1934-1996.

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The question of declining sperm density revisited: an analysis of 101 studies published 1934-1996.

Blood lead (BPb), activity of delta-aminolevulinic acid dehydratase (ALAD), erythrocyte protoporphyrin (EP), blood cadmium (BCd), serum zinc (SZn), seminal fluid zinc (SfZn), serum copper (SCu), and parameters of semen quality and of reproductive endocrine function were measured in 149 healthy male industrial workers 20-43 years of age. The group contained 98 subjects with slight to moderate occupational exposure to Pb and 51 reference subjects. All of the subjects lived in Zagreb, Croatia. Significant (p < 0.05) correlations of BPb, ALAD, and/or EP with reproductive parameters indicated a Pb-related decrease in sperm density, in counts of total, motile, and viable sperm, in the percentage and count of progressively motile sperm, in parameters of prostate secretory function (SfZn, acid phosphatase, and citric acid in seminal fluid), and an increase in abnormal sperm head morphology, serum testosterone, and estradiol. These associations were confirmed by results of multiple regression, which also showed significant (p < 0. 05) influence of BCd, SZn, SCu, smoking habits, alcohol consumption, or age on certain reproductive parameters. These effects were mainly of lower rank and intensity as compared to Pb-related reproductive effects, whereas BCd contributed to a decrease in sperm motility and an increase in abnormal sperm morphology and serum testosterone. No significant Pb- or Cd-related influence was found on levels of the lactate dehydrogenase isoenzyme LDH-C(4) and fructose in seminal fluid or on follicle-stimulating hormone, luteinizing hormone, and prolactin in serum. The seminal fluid concentrations of Pb (SfPb) and Cd (SfCd) were measured in 118 of the 149 subjects, and a highly significant (p < 0.0001) correlation was found between BPb and SfPb levels (r = 0.571) and between BCd and SfCd levels (r = 0.490). The overall study results indicate that even moderate exposures to Pb (BPb < 400 microg/L) and Cd (BCd < 10 microg/L) can significantly reduce human semen quality without conclusive evidence of impairment of male reproductive endocrine function.

Semen quality and reproductive endocrine function in relation to biomarkers of lead, cadmium, zinc, and copper in men.

Humans are exposed occupationally and environmentally to metal aerosols including lead (Pb2+) and cadmium (Cd2+). These toxicants accumulate in male reproductive organs. Epidemiological studies have been equivocal about effects of Pb2+ and Cd2+ on hormone concentrations, male fertility and sperm parameters. Comparison of Pb2+ and Cd2+ concentrations in fertile and infertile men are problematic. Problem areas include failure to control confounding variables, but genetic polymorphisms as in somatic diseases may modulate Pb2+ and Cd2+ damage. Multiple calcium (Ca2+) and potassium (K+) channel isoforms have been identified in human testes and spermatozoa. These Ca2+ and K+ channels are involved in early events of acrosome reactions. Ca2+ channel are susceptible to Cd2+ poisoning and K+ channels to Pb2+. These channels offer entry paths for metallic toxicants into mature spermatozoa. Ion channel polymorphisms may cause differential sensitivities to Cd2+ and Pb2+, explaining in part prospective blinded studies showing high Cd2+ in varicocele-related human infertility and high Pb2+ in unexplained infertility. In both forms of male infertility the ability to undergo an acrosome reaction decreases. Reverse transcriptase-polymerase chain reaction assays for Ca2+ and K+ channel isoforms may identify susceptibility subgroups with lower resistance to environmental exposures.

/pdf/male-infertility-and-environmental-exposure-to-lead-and-19cjbn9h14.pdf

Male infertility and environmental exposure to lead and cadmium

To determine if increased lead absorption was associated with sperm count suppression or perterbation of the hypothalamopituitary system, we compared battery workers (N=18), who were exposed to high airborne lead levels, with cement workers (N=18), who were exposed to ambient lead levels. Blood lead, urinary lead, semen lead, and zinc protoporphyrin concentrations were markedly elevated (p<.001) in battery workers. Battery workers had a significantly shifted (p<.025) frequency distribution of sperm count (median count, 45 vs. 73 × 106 cells/cc, respectively). There were no significant differences between the two groups in mean follicle-stimulating hormone, testosterone, prolactin, luteinizing hormone, or total neutral 17-ketosteroid levels. Potential confounding factors (alcohol, cigarette, and coffee consumption, frequency of intercourse, and days of abstinence prior to semen donation) were not significantly different between the two groups. These results suggest a direct toxic effect of increas...

Sperm count suppression without endocrine dysfunction in lead-exposed men.

Sulfuric acid is a colourless, odorless liquid, which causes typical injury patterns such as cutaneous and ocular burns, respiratory complications from inhalation, and ingestion injuries (coagulative necrosis of the mucosa, gastric and intestinal perforations) with significant dermal and mucosal injury because of its corrosive action. Most injuries caused by sulfuric acid ingestion are accidental, especially in the paediatric population. Intentional cases of ingestion have rarely been reported in adults as a method of suicide following a major depressive disorder. In this paper, we report the case of a 44-year-old woman who was found dead outside her home with a retained fillet knife embedded in her left chest wall and cutaneous chemical burns extending from her mouth down her chin and anterior torso. During the crime scene investigation, a half empty bottle of chemical drain cleaner containing concentrated sulfuric acid was found next to her body. An autopsy revealed chemical burns to the tongue, trachea, larynx, pharynx and oesophagus along with a blackish fluid in the peritoneal cavity. Histological analyses showed extensive corrosive changes in the gastrointestinal tract. Toxicological screening of blood and urine samples was negative; gastric contents contained a high quantity of concentrated (≈ 96%) sulfuric acid with a pH value of < 1.0. Death was attributed to shock following sulfuric acid ingestion. Circumstantial evidence and autopsy findings proved that the manner of death was suicidal. Complex suicides can be challenging for the forensic pathologist because of the plurality of methods used. The authors highlight the importance of systematical exhaustive postmortem investigation in order to ascertain the cause and manner of death in cases of planned complex suicide.

Roberto Gagliano Candela

Papers

Sperm count suppression without endocrine dysfunction in lead-exposed men.

Planned Complex Occupation-related Suicide by Sulfuric Acid Ingestion and Thorax Stab Wound: Case Report