A case study on co-exposure to a mixture of organic solvents in a Tunisian adhesive-producing company

Urinary trans-trans muconic acid (exposure biomarker to benzene) and hippuric acid (exposure biomarker to toluene) concentrations in Mexican women living in high-risk scenarios of air pollution

This study aimed to determine t,t-muconic acid (t,t-MA; exposure biomarker for benzene) and hippuric acid (HA; exposure biomarker for toluene) concentrations in the urine of women living in Mexico. In a cross-sectional study, apparently healthy women (n = 104) were voluntarily recruited from localities with a high risk of air pollution; t,t-MA and HA in urine were quantified using a high-performance liquid chromatography (HPLC) technique. Mean urinary levels of t,t-MA ranged from 680 to 1,310 μg/g creatinine. Mean values of HA ranged from 0.38 to 0.87 g/g creatinine. In conclusion, compared to data recently reported in literature, we found high urinary levels of t,t-MA and HA in assessed women participating in this study. We therefore deem the implementation of a strategy aimed at the reduction of exposure as a necessary measure for the evaluated communities.

Routine assessment of occupational exposure and its relation to semen quality in infertile men: a cross-sectional study

BACKGROUND/AIM

Concerns about the detrimental effects of occupational and environmental exposure on male reproductive function have been raised by reports of declining sperm quality over the last decades. The aim of this study was to investigate the association between altered semen parameters and exposure to occupational risk factors as assessed by questionnaire.

MATERIALS AND METHODS

We conducted a cross-sectional questionnaire-based study among a population of 2122 men who underwent andrological investigation for couple infertility. All participants were interviewed and their semen samples were analyzed. Information about medical history and occupational exposure was used to classify participants into exposed and unexposed groups.

RESULTS

Exposure to pesticides was associated with a significantly higher risk of asthenozoospermia (adjusted odds ratio [OR] = 1.6; 95% CI, 1.0-2.4) and necrozoospermia (OR = 2.6; 95% CI, 1.4-4.7). Exposure to cement was found to be correlated with a higher risk of oligozoospermia (OR = 1.1; 95% CI, 0.9-1.4). There was no association between semen impairment and exposure to solvents, excess heat, or mechanical vibrations.

CONCLUSION

We found an association between self-reported occupational exposure and altered semen parameters. These results support the usefulness of questionnaires for routine assessment and management of occupational exposures in infertile men.

Neuropsychological Symptoms among Workers Exposed to Toluene and Xylene in Two Paint Manufacturing Factories in Eastern Thailand

The study analyzed the exposure factors that may lead to neuropsychological symptoms among 92 workers who were exposed to xylene and toluene and 100 workers who were not exposed to the solvents. The airborne concentration of xylene and toluene was evaluated with personal passive badges. The levels of methyl hippuric acid and hippuric acid in urine were assessed, and interviews were performed to observe the neuropsychological symptoms that may result from exposure to the solvents. The result showed that the average concentration for the exposed group of xylene in the paint company working environment was 2.7 (SD = 2.4) ppm and the average concentration of toluene was 9.5 (SD = 10.4) ppm. The average level of methyl hippuric acid in urine was 78 (SD = 74.7) mg/g creatinine. Factors that affected the neuropsychological symptoms included the following. (1) The impact of age: the risk (adjusted odds ratio) for getting psychosomatic symptoms in persons over 40 and exposed to xylene was 9.5 and the aOR of those exposed to toluene was 8.3. (2) The impact of not providing personal protective equipment was found to be sleep disturbance; it was found that the aOR of those exposed to xylene was 3.9, and the aOR of those exposed to toluene was 4.4. In summary, periodic examination of workers by occupational physician is needed for detection of early neuropsychological effects, especially psychosomatic symptoms, and sleep disturbances.

Potential effects of environmental chemical contamination in congenital heart disease

There is compelling evidence that prenatal exposures to environmental xenobiotics adversely affect human development and childhood. Among all birth defects, congenital heart disease (CHD) is the most prevalent of all congenital malformations and remains the leading cause of death. It has been estimated that in most cases the causes of heart defects remain unknown, while a growing number of studies have indicated the potential role of environmental agents as risk factors in CHD occurrence. In particular, maternal exposure to chemicals during the first trimester of pregnancy represents the most critical window of exposure for CHD. Specific classes of xenobiotics (e.g. organochlorine pesticides, organic solvents, air pollutants) have been identified as potential risk factors for CHD. Nonetheless, the knowledge gained is currently still incomplete as a consequence of the frequent heterogeneity of the methods applied and the difficulty in estimating the net effect of environmental pollution on the pregnant mother. The presence of multiple sources of pollution, both indoor and outdoor, together with individual lifestyle factors, may represent a further confounding element for association with the disease. A future new approach for research should probably focus on individual measurements of professional, domestic, and urban exposure to physical and chemical pollutants in order to accurately retrace the environmental exposure of parents of affected offspring during the pre-conceptional and pregnancy periods.