Chlorinated pesticides and heavy metals in human semen

Exploring the Occurrence of Organic Contaminants in Human Semen through an Innovative LC-HRMS-Based Methodology Suitable for Target and Nontarget Analysis

Understanding the potential impact of organic contaminants on male fertility is crucial, yet limited studies have examined these chemicals in semen, with most focusing on urine and blood. To address this gap, we developed and validated a robust LC-HRMS methodology for semen analysis, with a focus on polar and semipolar chemicals. Our methodology enables the quantitative (or semiquantitative) analysis of >2000 chemicals being compatible with suspect and nontarget strategies and providing unprecedented insights into the occurrence and potential bioaccumulation of diverse contaminants in this matrix. We comprehensively analyzed exogenous organic chemicals and associated metabolites in ten semen samples from Spanish participants collected in an area with a large presence of the chemical industry included in the LED-FERTYL Spanish study cohort. This investigation revealed the presence of various contaminants in semen, including plastic additives, PFAS, flame retardants, surfactants, and insecticides. Notably, prevalent plastic additives such as phthalic acid esters and bisphenols were identified, indicating potential health risks. Additionally, we uncovered previously understudied chemicals like the tire additive 2-mercaptobenzothiazole and specific organophosphate flame retardants. This study showcases the potential of our methodology as a valuable tool for large-scale cohort studies, providing insights into the association between contaminant exposure and the risk of male fertility impairments.

Impact of Heavy Metals on Human Male Fertility-An Overview

Heavy metals are endocrine disruptors which interfere with processes mediated by endogenous hormones of the organism, negatively affecting endocrine functions. Some studies have correlated heavy metal exposure with male infertility. However, the number of studies conducted on humans are limited. Therefore, the aim of this study is to summarize the current knowledge on how heavy metals influence human male fertility. Hence, three distinct databases were consulted—PubMed, Scopus and Web of Science—using single keywords and combinations of them. The total number of identified articles was 636. Nevertheless, by using the inclusion and exclusion criteria, 144 articles were finally included in this work. Results display that the development of adequate instruments for heavy metal assessment may play an important function in human male fertility diagnosis and treatment. Furthermore, clinical trials could be useful to confirm the role of heavy metals in human male fertility diagnosis. Overall, further research is required to fully understand the molecular and cellular basis of the influence of environmental and occupational exposure to heavy metals on human male infertility and reproductive outcomes.

Turmeric and vitamin C mitigate testicular atrophy induced by lead diacetate via regulation of GRP-78/17β-HSD pathways in rat's model

Occupational and ecological contacts to lead persist as a universal concern. Lead alters most of the physiological processes via enhancing oxidative stress. Thus, this study was purposed to assess the influence of turmeric (TMRC) and/or vitamin C (VIT-C) on Lead diacetate (Lead diAC)-induced testicular atrophy with an emphasis on oxidative stress, inflammation, BAX/STAR and GRP-78/17β-HSD signalling. Rats were injected with Lead diAC and then treated with TMRC and/or VIT-C orally for 1 week. Lead diAC decreased serum testosterone and testicular glutathione levels. It also decreased superoxide dismutase activity. On the contrary, levels of malondialdehyde, tumour necrosis factor-α, IL-1β and caspase-3 were increased. mRNA levels and protein expressions of GRP-78 and BAX were upregulated, while the expression of both steroidogenic acute regulatory protein and 17β-HSD were downregulated. DNA fragmentation was increased as well. These changes were further confirmed by histopathological findings. Supplementation with TMRC and/or VIT-C ameliorated all of the above parameters. In Conclusion: TMRC or VIT-C specially in combination group prevents Lead diAC testicular damage via reduction of oxidative injury as well as inflammation, downregulation of GRP-78/BAX and upregulation of 17β-HSD and STAR expression as well as improvement in the histological architecture of the testis.

Effect of neonatal exposure to endosulfan on myometrial adaptation during early pregnancy and labor in rats

Proper myometrial adaptation during gestation is crucial for embryo implantation, pregnancy maintenance and parturition. Previously, we reported that neonatal exposure to endosulfan alters uterine development and induces implantation failures. The present work investigates the effects of endosulfan exposure on myometrial differentiation at the pre-implantation period, and myometrial activation during labor. Newborn female rats were s.c. injected with corn oil (vehicle) or 600 μg/kg/day of endosulfan (Endo600) on postnatal days (PND) 1, 3, 5 and 7. On PND90, the rats were mated to evaluate: i) the myometrial differentiation on gestational day 5 (GD5, pre-implantation period), by assessment myometrial histomorphology, smooth muscle cells (SMCs) proliferation, and expression of proteins involved in myometrial adaptation for embryo implantation (steroid receptors, Wnt7a and Hoxa10); ii) the timing of parturition and myometrial activation during labor by determining the uterine expression of contraction-associated genes (oxytocin receptor, OTXR; prostaglandin F₂α receptor, PTGFR and connexin-43, Cx-43). Endosulfan decreased the thickness of both myometrial layers, with a concomitant decrease in the collagen remodeling. Blood vessels relative area in the interstitial connective tissue between muscle layers was also decreased. Endo600 group showed lower myometrial proliferation in association with a downregulation of Wnt7a and Hoxa10. Although in all females labor occurred on GD23, the exposure to endosulfan altered the timing of parturition, by inducing advancement in the initiation of labor. This alteration was associated with an increased uterine expression of OTXR, PTGFR and Cx-43. In conclusion, neonatal exposure to endosulfan produced long-term effects affecting myometrial adaptation during early pregnancy and labor. These alterations could be associated with the aberrant effects of endosulfan on the implantation process and the timing of parturition.

Heavy metals in soils of Hechuan County in the upper Yangtze (SW China): Comparative pollution assessment using multiple indices with high-spatial-resolution sampling

In order to assess heavy metals (HMs) in soils of the upper Yangtze Basin, a very high-spatial-resolution sampling (582 soil samples) was conducted from Hechuan County, an important agricultural practice area in the Southwest China. Multiple indices including geoaccumulation index (I_geo), enrichment factor (EF), sediment pollution index (SPI) and risk index (RI), as well as multivariate statistics were employed for pollution assessment and source identification of HMs in soils. Our results demonstrated that the averages of eight HMs decreased in the following order: Zn (82.8 ± 15.9) > Cr (71.6 ± 12.2) > Ni (32.1 ± 9.89) > Pb (27.6 ± 13.8) > Cu (25.9 ± 11.8) > As (5.48 ± 3.42) > Cd (0.30 ± 0.077) > Hg (0.082 ± 0.092). Averages of HMs except Cd were lower than threshold value of Environmental Quality Standard for Soils, while 43% of total samples had Cd concentration exceeding the national standard, 1% of samples for Hg and 5% samples for Ni, moreover, Cd and Hg averages were much higher than their background levels. I_geo and EF indicated that their levels decreased as follows: Cd > Hg > Zn > Pb > Ni > Cu > Cr > As, with moderate enrichments of Cd and Hg. RI indicated that 61.7% of all samples showed moderate risk, while 6.5% of samples with greater than considerable risk due to human activities should be paid more attention. Multivariate analysis showed lithogenic source of Cu, Cr, Ni and Zn, while Cd and Hg were largely contributed by anthropogenic activities such as agricultural practices. Our study would be helpful for improving soil environmental quality in SW, China, as well as supplying modern approaches for other areas with soil HM pollution.

The Catsper channel and its roles in male fertility: a systematic review

The Catsper channel is a sperm-specific, Ca²⁺-permeable, pH-dependent, and low voltage-dependent channel that is essential for the hyperactivity of sperm flagellum, chemotaxis towards the egg, capacitation and acrosome reaction. All of these physiological events require calcium entry into sperm cells. Remarkably, Catsper genes are exclusively expressed in the testis during spermatogenesis, and are sensitive to ion channel-induced pH change, such as NHEs, Ca²⁺ATPase, K⁺ channel, Hv1 channel and HCO₃^- transporters. Furthermore, the Catsper channel is regulated by some physiological stimulants, such as progesterone, cyclic nucleotides (e.g., cAMP, cGMP), zona pellucida (ZP) glycoproteins and bovine serum albumin (BSA). All of these factors normally stimulate Ca²⁺ entry into sperm through the Catsper channel. In addition, the Catsper channel may be a potential target for male infertility treatment or contraception. This review will focus on the structure, functions, regulation mechanisms and medicinal targets of the Catsper channel.

Toxic metals signature in the human seminal plasma of Pakistani population and their potential role in male infertility

Aims of this study were to provide firsthand data on the incidence of trace metals in human seminal plasma and find possible correlations between levels of toxic metals and semen quality of Pakistani population. Human semen samples were collected from male partners of couples undergoing infertility assessment at the National Institute of Health Islamabad (Pakistan). We investigated seventy-five seminal plasma samples, which were further categorized into three groups (normozoospermia, oligozoospermia and azoospermia) according to WHO guidelines. The concentration of 17 different toxic metals in human seminal plasma was determined simultaneously by using Inductively coupled plasma mass spectrometry (ICP-MS). Out of 17 trace metals, Cd and Ni showed significant difference (p < 0.05) among three monitored groups. Ni and Cd concentrations in the seminal plasma were negatively correlated with sperm concentration (r = -0.26, -0.29) and motility (r = -0.33, -0.37), respectively. This study suggested that exposure of Ni and Cd is mainly related with the consumption of contaminated dietary items, including ghee (cooking oil), flour and other agri-products. In some semen samples, the concentrations of Sn, V, Cu, Pb, Cr and Hg exhibited high levels suggesting a recent human exposure to surrounding sources. In Pakistani human semen samples, the levels of trace metals were lower and/or comparable to that found in populations of other countries. The results show the first evidence of the effect of toxic metals on semen quality and male infertility in Pakistan.

Association between environmental exposure to p, p'-DDE and lindane and semen quality

Scientific concern exists about the toxic effect of dichlorodiphenyldichloroethylene (p, p'-DDE) and lindane on male infertility, and the mechanism underlying male reproductive toxicity of this pesticide remains unanswered. We investigated not only the possible association between the chlorinated pesticide levels and semen quality in nonoccupationally exposed men, but also the probable mode of action using mitochondrial membrane potential (MMP), reactive oxygen species (ROS), lipid peroxidation (LPO), and sperm chromatin structure assay (SCSA). A study in 278 men (21-40 years old) who visited Obstetrics and Gynecology Department, KGMU, Lucknow, for semen analysis was conducted. We performed semen analysis according to the WHO guidelines, while p, p'-DDE and lindane analysis was done by the GLC and LPO by the spectrophotometer, and the sperm mitochondrial status, ROS, and SCSA with the flow cytometer. The questionnaire data showed no significant difference in the demographic characteristics between the two groups, i.e., trying to conceive >1 year and proven fertility. However, a significant difference in the concentration of p, p'-DDE and lindane was observed between the groups. When the subjects were divided among four categories by quartile of exposure, the subjects in the highest quartile showed low sperm motility as compared to the subjects in the lowest quartile. Pearson's correlation showed a significant negative correlation between semen p, p'-DDE, lindane level, and sperm quality and positive association with the number of cells with depolarized mitochondria, elevation in ROS production and LPO, and DNA fragmentation index (DFI). The findings are suggestive that these toxicants might cause a decline in semen quality, and these effects might be ROS, LPO, and mitochondrial dysfunction mediated.

Occupational exposure to pesticides and consequences on male semen and fertility: a review

Exposure to pesticides affects many body organs including reproductive system. Disorder of the reproductive system leads to infertility and therefore has been in the center of attention within the recent decades. Pesticides are one of the compounds that might reduce the semen quality in the exposed workers according to current knowledge. Although many underlying mechanisms have been proposed, the mechanisms of action are not clarified yet. The object of the present review was to criticize all the results of studies which evaluated the pesticide effects on male reproductive system. Results indicate that semen changes are multifactorial in the workers exposed to pesticides as there are numerous factors affecting sperm quality in occupational exposures. Majority of pesticides including organophosphoruses affect the male reproductive system by mechanisms such as reduction of sperm density and motility, inhibition of spermatogenesis, reduction of testis weights, reduction of sperm counts, motility, viability and density, and inducing sperm DNA damage, and increasing abnormal sperm morphology. Reduced weight of testes, epididymis, seminal vesicle, and ventral prostate, seminiferous tubule degeneration, change in plasma levels of testosterone, follicle-stimulating hormone (FSH), and luteinizing hormone (LH), decreased level and activity of the antioxidant enzymes in testes, and inhibited testicular steroidogenesis are other possible mechanisms. Moreover, DDT and its metabolites have estrogenic effects on males. Although effect of pesticides on sperm quality is undeniable, well-designed long-term studies are needed to elucidate all the possible affecting variables such as socioeconomic, cultural, nutritional, occupational, physical, and clinical characteristics alongside pesticides.

Modulation of plant growth and metabolism in cadmium-enriched environments

Cadmium (Cd) is a water soluble metal pollutant that is not essential to plant growth.It has attracted attention from soil scientists and plant nutritionists in recent years because of its toxicity and mobility in the soil-plant continuum. Even low levels of Cd (0.1-1 J.!M) cause adverse effects on plant growth and metabolism. Cadmium is known to trigger the synthesis of reactive oxygen species, hinder utilization, uptake and transport of essential nutrients and water, and modify photosynthetic machinery,thereby resulting in plant tissue death. Although the effects of Cd are dose- as well as plant species-dependent, some plants show Cd tolerance through a wide range of cellular responses. Such tolerance results from synthesis of osmolytes,generation of enzymatic and non-enzymatic antioxidants and metal-detoxifying peptides, changes in gene expression, and metal ion homeostasis and compartmentalization of ligand-metal complexes. Cd toxicity in plants produces effects on chlorophyllbio synthesis, reduces photosynthesis, and upsets plant water relations and hormonal and/or nutritional balances. All of these effects on plants and on plant metabolism ultimately reduce growth and productivity.In this review, we describe the extent to which Cd affects underlying metabolic processes in plants and how such altered processes affect plant growth. We review the sources of Cd contamination, its uptake, transportation and bioavailability and accumulation in plants, and its antagonistic and synergistic effects with other metals and compounds. We further address the effects of Cd on plant genetics and metabolism,and how plants respond to mitigate the adverse effects of Cd exposure, as well as strategies(e.g., plant breeding) that can reduce the impact of Cd contamination on plants.

Semen quality of environmentally exposed human population: the toxicological consequence

Human data on the relationship of semen quality with pesticide and metals are mostly inconsistent. The purpose of the study is to confirm the toxicity of organochlorine pesticide β- and γ-hexachlorocyclohexane (HCH), DDE and DDD, and metals lead or cadmium on sperm motility in epidemiological study among fertile and infertile men and to determine whether in vivo and in vitro results are in the same direction. Semen analysis and estimation of the toxicants were done in 60 fertile and 150 infertile men. In the in vitro studies, sperm were exposed to the highest levels of these toxicants found in vivo, as well as five and ten times higher, and to the mixture of all compounds. The study assesses sperm viability and motility for a period ranging between 30 min and 96 h. Epidemiological data showed an inverse correlation of toxicant with sperm motility. In vitro study showed that γ-HCH and lead after 12 h, cadmium after 8 h, and coexposure to toxicants after 6 h of exposure caused significant concentration- and duration-dependent decline in sperm motility. Data of in vitro study were concurrent with epidemiological finding that might be useful in establishing the possible association between exposure and effect of these selected pollutants on sperm motility.

p,p'-DDE activates CatSper and compromises human sperm function at environmentally relevant concentrations

STUDY QUESTION

Is the environmental endocrine disruptor p,p′-dichlorodiphenyldichloroethylene (p,p′-DDE) able to induce non-genomic changes in human sperm and consequently affect functional sperm parameters?

SUMMARY ANSWER

p,p′-DDE promoted Ca²⁺ flux into human sperm by activating CatSper channels even at doses found in human reproductive fluids, ultimately compromising sperm parameters important for fertilization.

WHAT IS KNOWN ALREADY

p,p′-DDE may promote non-genomic actions and interact directly with pre-existing signaling pathways, as already observed in other cell types. However, although often found in both male and female reproductive fluids, its effects on human spermatozoa function are not known.

STUDY DESIGN, SIZE, DURATION

Normozoospermic sperm samples from healthy individuals were included in this study. Samples were exposed to several p,p′-DDE concentrations for 3 days at 37°C and 5% CO₂in vitro to mimic the putative continuous exposure to this toxicant in the female reproductive tract in vivo. Shorter p,p′-DDE incubation periods were also performed in order to monitor sperm rapid Ca²⁺ responses. All experiments were repeated on a minimum of five sperm samples from different individuals.

PARTICIPANTS/MATERIALS, SETTING, METHODS

All healthy individuals were recruited at the Biosciences School, University of Birmingham, the Medical Research Institute, University of Dundee and in the Human Reproduction Service at University Hospitals of Coimbra. Intracellular Ca²⁺ concentration ([Ca²⁺]_i) was monitored by imaging single spermatozoa loaded with Oregon Green BAPTA-1AM and further whole-cell patch-clamp recordings were performed to validate our results. Sperm viability and acrosomal integrity were assessed using the LIVE/DEAD sperm vitality kit and the acrosomal content marker PSA-FITC, respectively.

MAIN RESULTS AND THE ROLE OF CHANCE

p,p′-DDE rapidly increased [Ca²⁺]_i (P < 0.05) even at extremely low doses (1 pM and 1 nM), with magnitudes of response up to 200%, without affecting sperm viability, except after 3 days of continuous exposure to the highest concentration tested (P < 0.05). Furthermore, experiments performed in a low Ca²⁺ medium demonstrated that extracellular Ca²⁺ influx was responsible for this Ca²⁺ increase (P < 0.01). Mibefradil and NNC 55-0396, both inhibitors of the sperm-specific CatSper channel, reversed the p,p′-DDE-induced [Ca²⁺]_i rise, suggesting the participation of CatSper in this process (P < 0.05). In fact, whole-cell patch-clamp recordings confirmed CatSper as a target of p,p′-DDE action by monitoring an increase in CatSper currents of >100% (P < 0.01). Finally, acrosomal integrity was adversely affected after 2 days of exposure to p,p′-DDE concentrations, suggesting that [Ca²⁺]_i rise may cause premature acrosome reaction (P < 0.05).

LIMITATIONS, REASONS FOR CAUTION

This is an in vitro study, and caution must be taken when extrapolating the results.

WIDER IMPLICATIONS OF THE FINDINGS

A novel non-genomic p,p′-DDE mechanism specific to sperm is shown in this study. p,p′-DDE was able to induce [Ca²⁺]_i rise in human sperm through the opening of CatSper consequently compromising male fertility. The promiscuous nature of CatSper activation may predispose human sperm to the action of some persistent endocrine disruptors.

STUDY FUNDING/COMPETING INTEREST(S)

The study was supported by both the Portuguese National Science Foundation (FCT; PEst-C/SAU/LA0001/2011) and the UK Wellcome Trust (Grant #86470). SM was supported by the Infertility Research Trust. RST is a recipient of a PhD fellowship from FCT (SFRH/BD/46002/2008). None of the authors has any conflict of interest to declare.

Determination of polybrominated diphenyl ethers in human semen

Some persistent organic pollutants (POPs) have been found in human semen but until this point it was unclear whether polybrominated diphenyl ethers (PBDEs) could be detected in human semen. In this study, PBDEs were found for the first time in human semen samples (n=101) from Taizhou, China. The concentrations of total PBDEs (∑PBDEs) varied from 15.8 to 86.8 pg/g ww (median=31.3 pg/g ww) and 53.2 to 121 pg/g ww (median=72.3 pg/g ww) in semen and blood samples, respectively. The ∑PBDE level in semen was about two times lower than in human blood, which was different in the distribution in the two matrices from other POPs. A correlation of ∑PBDE concentration was found between paired semen and in blood. The results suggest that semen could be used to detect PBDE burden in human body as a non-invasive matrix. In addition, the levels of BDE-209 and BDE-153, especially the latter, were much higher in blood than in semen, while the levels of BDE-28, BDE-47 and BDE-99 were comparable in the two matrices, suggesting that low brominated congeners could be more easily transferred to semen than high brominated congeners. Considering different toxicities among the PBDE congeners, it might be more significant to measure PBDEs in semen than in blood for evaluating male reproduction risks of PBDEs.

Objective assessment of an ionic footbath (IonCleanse): testing its ability to remove potentially toxic elements from the body

Ionic footbaths are often used in holistic health centres and spas to aid in detoxification; however, claims that these machines eliminate toxins from the body have not been rigorously evaluated. In this proof-of-principle study, we sought to measure the release of potentially toxic elements from ionic footbaths into distilled and tap water with and without feet. Water samples were collected and analyzed following 30-minute ionic footbath sessions without feet using both distilled (n = 1) and tap water (n = 6) and following four ionic footbaths using tap water (once/week for 4 weeks) in six healthy participants. Urine collection samples were analyzed at four points during the study. Hair samples were analyzed for element concentrations at baseline and study conclusion. Contrary to claims made for the machine, there does not appear to be any specific induction of toxic element release through the feet when running the machine according to specifications.

Non-invasive matrices in human biomonitoring: a review

Humans and other living organisms are exposed to a variety of chemical pollutants that are released into the environment as a consequence of anthropogenic activities. Environmental pollutants are incorporated into the organism by different routes and can then be stored and distributed in different tissues, which leads to an internal concentration that can induce different alterations, adverse effects and/or diseases. Control measures should be taken to avoid these effects and human biomonitoring is a very useful tool that can contribute to this aim. Human biomonitoring uses different matrices to measure the target chemicals depending on the chemical, the amount of matrix necessary for the analysis and the detection limit (LOD) of the analytical technique. Blood is the ideal matrix for most chemicals due to its contact with the whole organism and its equilibrium with organs and tissues where chemicals are stored. However, it has an important disadvantage of being an invasive matrix. The development of new methodology and modern analytical techniques has allowed the use of other matrices that are less or non-invasive, such as saliva, urine, meconium, nails, hair, and semen or breast milk. The presence of a chemical in these matrices reflects an exposure, but correlations between levels in non-invasive matrices and blood must be established to ensure that these levels are related to the total body burden. The development of new biomarkers that are measurable in these matrices will improve non-invasive biomonitoring. This paper reviews studies that measure Cd, Pb, Hg, polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polycyclic aromatic hydrocarbons (PAHs), polybrominated diphenyl ethers (PBDEs), organochlorine pesticides and phthalates in non-invasive matrices, the most used techniques for measurements and what alternative techniques are available.

Pre- and post-conception pesticide exposure and the risk of birth defects in an Ontario farm population

The use of pesticides has enhanced the health and economies of nations around the world by improving crop production. However, pesticides may pose health risks, particularly to the fetus and young children. In a secondary analysis of the Ontario Farm Family Health Study, we explored the relationship between birth defects and parental pesticide exposure during the 3 months prior to conception and the first trimester of pregnancy. A total of 3412 pregnancies were included in the study. Logistic regression fit by maximum likelihood was used in the analysis. The results showed that pre-conception exposure to both cyanazine (odds ratio=4.99, 95% confidence interval: 1.63-15.27) and dicamba (OR=2.42, 95% CI: 1.06-5.53) were associated with increased risk of birth defects in male offspring. Nevertheless, given the self-reported nature of the exposure and outcomes in this study, the present findings should be considered primarily as hypothesis generating, requiring verification in subsequent investigations.

Chlorinated pesticide concentration in semen of fertile and infertile men and correlation with sperm quality

In recent years controversy has evolved regarding the role of environmental pollutants especially chlorinated pesticides and heavy metals on male infertility. Previous data generated on the correlation of chlorinated pesticides with human semen are scarce and controversial. The objective is to explore the possibility of correlation if any between the chlorinated pesticides and sperm count and motility. Semen analysis were performed in 50 samples collected each from fertile and infertile men and pesticides estimation for dichlorodiphenyltrichloroethane (DDT) and its metabolites dichloro-2,2-bis(p-chlorophenyl) ethylene (DDE); 1,1,1-trichloro-2,2-bis(p-chlorophenyl ethane) (pp'DDT); 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (pp'DDD), 1,1,1-trichloro-2-(o-chlorophenyl)-2-(p-chlorophenyl)ethane (op'DDT), aldrin, hexachlorocyclohexane (HCH) isomers alpha (α), beta (β), gamma (γ), delta (δ) were done by gas liquid chromatography. The higher concentrations of pesticide, viz. α-, β-, γ-, δ-HCH, DDT and its metabolites (pp'DDE and pp'DDD) were detected in semen samples of infertile males. The data showed significant association between β-HCH, γ-HCH, pp'DDE, pp'DDD with semen quality parameters.

Correlation of chlorinated pesticides concentration in semen with seminal vesicle and prostatic markers

Semen samples of fertile and infertile men were analysed by gas liquid chromatography (GLC) for the presence of dichlorodiphenyltrichloroethane (DDT) and its metabolites (1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene) (pp'-DDE); (1,1,1-trichloro-2,2-bis(p-chlorophenyl ethane) (pp'-DDT); (1,1-dichloro-2,2 bis(p-chlorophenyl) ethane) (pp'-DDD); (1,1,1-trichloro-2-(o-chlorophenyl)-2-(p-chlorophenyl) ethane) (op'-DDT), hexachlorocyclohexane (HCH) and its isomers alpha (alpha), beta (beta), gamma (gamma), delta (delta) and aldrin. The biochemical analysis of seminal vesicle and prostatic marker was done by spectrophotometer. The concentrations of alpha-, beta-, gamma-HCH, pp'-DDE and pp'-DDD were higher in the semen of infertile than in that of fertile men. An elevation in the fructose level along with decrease in the gamma-glutamyl transpeptidase and acid phosphatase activity was noticed in infertile men as compared to fertile subjects. The data showed correlation between alpha-, beta-, gamma-HCH, pp'-DDE, pp'-DDD and seminal vesicle marker fructose and prostatic marker gamma-gluatamyl transpeptidase and acid phosphatase in infertile men. The study suggests that the chlorinated pesticides may influence the semen quality by affecting the seminal and prostatic functions in infertile men.

Parental lead exposure and total anomalous pulmonary venous return

BACKGROUND

Investigators from the Baltimore-Washington Infant Study (BWIS) reported an association between self-reported maternal lead exposure and total anomalous pulmonary venous return (TAPVR) in their offspring. This association was further evaluated in the BWIS population using a more sensitive exposure estimate.

METHODS

Cases included 54 live-born infants with TAPVR; controls were a stratified random sample of 522 live-born infants from the BWIS control group. Parental lead exposure was based on three assessment methods, including: an industrial hygiene assessment, an a priori job exposure matrix, and self-reported exposures. A parent was classified as exposed to lead if he/she was classified as exposed by any one of the assessment methods.

RESULTS

Approximately 17% of case mothers and 11% of control mothers were classified as exposed to lead during the three months prior to conception through the first trimester (odds ratio [OR], 1.57; 95% confidence interval [CI], 0.64-3.47). Among fathers, 61% of case fathers and 46% of control fathers were classified as exposed to lead during the six months prior to conception (paternal critical period) (OR, 1.83; 95% CI, 1.00-3.42). During the paternal critical period, when only the father was exposed compared to neither parent exposed, the OR for any lead exposure and TAPVR was 1.65 (95% CI, 0.84-3.25).

CONCLUSIONS

This study supports a possible association between paternal lead exposure and TAPVR. Further studies are warranted using validated assessment methods for occupational and nonoccupational lead exposures to corroborate this association and to elucidate the possible biological mechanism. Birth Defects Research (Part A), 2004.

Lead and cadmium concentration in the seminal plasma of men in the general population: correlation with sperm quality

The concentration of lead and cadmium in the seminal plasma of men in the general population, including fertile and infertile subjects, was measured. Semen samples were categorised as demonstrating oligospermia (sperm concentration < 20 x 10(6)/ml), asthenospermia (<50% motilesperm), oligoasthenospermia (a combination of the two criteria), and azoospermia (no sperm). An increase in lead and cadmium levels was observed in infertile men and there was a significant negative correlation of cadmium and lead semen concentration with sperm motility and sperm concentration in oligoasthenospermic men.

[Cytotoxic effects of lead on the endocrine and exocrine sexual function of pubescent male and female rats. Demonstration of apoptotic activity]

This study deals with the impact of chronic exposure to lead on male and female fertility in rats. Male and female rats (3 months old) were fed on commercial tablets (SICO, Sfax). For drinking, some rats were given distilled water (T = controls), the other ones were given distilled water enriched with lead acetate, either 3 (P1 group) or 6 mg ml-1 (P2 group), for 15, 30, 45, 60 or 90 days. In male rats, absolute and relative weights of testis, epididymis, prostate and seminal vesicles were found to significantly decrease at day 15 in the P2 group and at day 45 in the P1 group. However, at day 60, these absolute and relative weights returned to control values. Lead-induced pathological changes in spermatogenesis were observed at day 15 by histological study: arrest of cell germ maturation, changes in the Sertoli cells, and presence of apoptotic cells revealed by borated toluidine blue in the testis. Presence of lead deposits was observed after histochemical staining using sodium rhodizonate. Serum testosterone level was found to be lowered at day 15 in both (P1) and (P2) groups, to display a peak at day 60, then to return to controls values, in spite of the continuation of the treatment. In female rats, absolute and relative weights of ovary and uterus were found unchanged. The vaginal smears practiced in females revealed the oestrus phase in all groups. Exposed females were mated with control males, and fecundity was assessed 15 days later by counting the number of pregnancies and the number of concepti per pregnancy. Fertility was found to be reduced in females of P1 and P2 groups as compared to control females (T group). Lead level in blood was found to be poorly correlated with the level of poisoning, whereas lead accumulation in tail was found to be dose-dependent. Therefore, lead accumulation in tail appears as a more reliable biomarker of exposure to lead. In summary, our study shows that chronic exposure to lead causes a double sexual disorder in rats: first, disorder deals with the hormonal function, which is affected at the early stages of poisoning, but is rapidly corrected; second, disorder deals with the genital tract, affecting the testis and the ovary, resulting in a reduced fertility in both P1 and P2 females, in spite of the presence of a normal oestrus. The cytotoxic effect of lead in males seems to be related to an apoptotic process.