Sona Wimmerova

Exposure to polychlorinated biphenyls and hearing impairment in children.

The objective of this cross-sectional epidemiological study was to assess if long-term exposure to polychlorinated biphenyls (PCBs) is associated with hearing impairment. Four hundred and thirty-three children aged 8-9 years residing in an area polluted by PCBs in Eastern Slovakia were examined otoscopically, tympanometrically and by pure tone audiometry. PCB levels in their serum were determined by gas chromatography. Transient otoacoustic emissions (TEOAE) were measured in a subgroup of 161 children. The mean of the sum of PCB concentrations in serum was 528.2ng/g serum lipids (median 321ng/g serum lipids). Serum PCB concentrations were associated with an increase of hearing threshold at low frequencies and a negative correlation between serum PCBs and the amplitude of TEOAE response was observed in the uppermost tertile of children grouped with regard to serum PCBs, not related to thyroid hormone levels. It was concluded that long-term environmental exposure to PCBs is associated with subclinical but diagnosable hearing deficits.

Phthalate exposure and health-related outcomes in specific types of work environment.

Many toxic substances in the workplace can modify human health and quality of life and there is still insufficient data on respiratory outcomes in adults exposed to phthalates. The aim of this work was to assess in waste management workers from the Nitra region of Slovakia (n = 30) the extent of exposure to phthalates and health-related outcomes. Four urinary phthalate metabolites mono(2-ethylhexyl) phthalate (MEHP), monobutyl phthalate (MnBP), monoethyl phthalate (MEP) and monoisononyl phthalate (MiNP) were determined by high-performance liquid chromatography with mass spectrometry (HPLC-MS/MS). Urinary concentration of MEHP was positively associated with ratio of forced expiratory volume in 1 s to forced vital capacity % (FEV1/FVC) (r = 0.431; p = 0.018) and MiNP with fat free mass index (FFMI) (r = 0.439; p = 0.015). The strongest predictor of pulmonary function was the pack/year index as smoking history that predicted a decrease of pulmonary parameters, the FEV1/FVC, % of predicted values of peak expiratory flow (PEF % of PV) and FEV1 % of PV. Unexpectedly, urinary MEHP and MINP were positively associated with pulmonary function expressed as PEF % of PV and FEV1/FVC. We hypothesize that occupational exposure to phthalates estimated from urinary metabolites (MEHP, MiNP) can modify pulmonary function on top of lifestyle factors.

Respiratory toxicity of Fe3O4 nanoparticles: experimental study

Abstract Introduction: In the medical field, nanoparticles (NP) Fe3O4 are currently considered to be a relatively inert carrier for therapeutic and diagnostic pharmaceuticals, and they are also presumed for intravenous (i.v.) administration. Because they have nano dimensions, they probably can penetrate through various membranes and pass from the bloodstream to other organs in the body (Borm P, Muller-Schulte D. Nanoparticles in medicine, 2007, Chapter 21, pp. 387–413, Particle Toxicology, ed. Donaldson K, Borm P, Taylor & Francis Group, USA, 434 p., ISBN 0-8493-5092-1). Therefore, in our experiment, we have examined the impact of a NP Fe3O4 instilled i.v. (to a tail vein of an animal) on the select parameters of bronchoalveolar lavage (BAL). The aim of our study was to determine whether the NP investigated by us, pass through the vascular system to the respiratory tract, and if so, how they affect the selected inflammatory and cytotoxic parameters of BAL. Materials and methods: Wistar rats were intravenously given a suspension of Fe3O4 and after time intervals of 1, 7, 14 and 28 days, the animals were sacrificed, BAL was performed and selected inflammatory and cytotoxic BAL parameters were examined. Conclusion: Based on the results obtained by us, Fe3O4 NP exposure, compared to the control, induced inflammatory response, the cytotoxic damage and respiratory toxicity. The results further show that Fe3O4 NP, 28 days after i.v. instillation, were eliminated from the respiratory tract by defense mechanisms.

Immune System and Environmental Xenobiotics - The Effect of Selected Mineral Fibers and Particles on the Immune Response

Mineral fibers and particles are finding growing applications in industry and thus entering into the human environment. The utility of using such products for various purposes is promising but detailed information related to immune safety is needed. Immunotoxic effects may be displayed as immunosuppression, immunostimulation, hypersensitivity and autoimmunity. Humans may be exposed to fibers and particles from a variety of sources, including occupational settings, ambient air, consumer products, drinking water and food. This chapter is dedicated to the effect of inhalation exposure to asbestos, rock wool, glass wool, ceramic fibers and nickel oxide particles on the immune system.