Miklós Náray

Age dependent accumulation of cadmium in the human ovary

Cadmium (Cd) was determined by atomic absorption spectrophotometry in small pieces (< 1 g) of healthy human ovaries excised for histologic examination. Cd levels in the ovary increased linearly between 30 and 65 years of age. Below 30 years, there was no age dependent increase and over 65 a tendency was observed for ovarian Cd levels to decrease. There was no difference in the Cd content of fresh luteal and nonluteal tissue taken from regularly cycling ovaries. In smokers, the amount of Cd in the ovaries was elevated compared to nonsmokers. In multiparous women (more than 3 children) a tendency of decreased Cd ovarian levels was observed. There was no difference between ovarian Cd content of physical and mental workers. It can be proposed that Cd may be a risk factor for conception and pregnancy in women in their forties.

Lead accumulation in human ovarian follicular fluid, and in vitro effect of lead on progesterone production by cultured human ovarian granulosa cells

Lead content of ovarian follicular fluid obtained from 23 women was determined by atomic absorption spectrophotometry. In an in vitro experiment the direct effect of lead on the morphology and on progesterone (P) production by cultured granulosa cells of six women was investigated. Follicular fluid and granulosa cells were obtained from follicular aspirates of women undergoing in vitro fertilization (IVF) and embryo transfer (ET). Granulosa cells were cultured for 48 h to form monolayers in the presence or absence of lead acetate (100-1600 µ M). The effect of the metal proved to be concentration dependent. While 100-400 µ M lead had no effect on the integrity of the monolayer, concentrations as high as 800 µ M or higher inhibited cell adhesion and induced detachment of cells. The lead levels found in follicular fluid were 11.29 - 1.38 µg/L (0.056 - 0.007 µ M). With lead in vitro at 1600 µ M (331.5 mg/L) there resulted a significant decrease in P production by granulosa cells. This concentration is very much higher than that measured in follicular fluid of IVF/ET patients, specifically nonexposed to lead, and even higher than mean blood levels reported by others in high exposure groups. In conclusion, lead seems not to exert a specific effect on the steroidogenesis by cultured human granulosa cells. Therefore, the lead levels measured in the ovarian follicular fluid seem not to pose a hazard with respect to progesterone secretion by the ovary.

Mercury analysis in hair: Comparability and quality assessment within the transnational COPHES/DEMOCOPHES project

Human biomonitoring (HBM) is an effective tool for assessing actual exposure to chemicals that takes into account all routes of intake. Although hair analysis is considered to be an optimal biomarker for assessing mercury exposure, the lack of harmonization as regards sampling and analytical procedures has often limited the comparison of data at national and international level. The European-funded projects COPHES and DEMOCOPHES developed and tested a harmonized European approach to Human Biomonitoring in response to the European Environment and Health Action Plan. Herein we describe the quality assurance program (QAP) for assessing mercury levels in hair samples from more than 1800 mother-child pairs recruited in 17 European countries. To ensure the comparability of the results, standard operating procedures (SOPs) for sampling and for mercury analysis were drafted and distributed to participating laboratories. Training sessions were organized for field workers and four external quality-assessment exercises (ICI/EQUAS), followed by the corresponding web conferences, were organized between March 2011 and February 2012. ICI/EQUAS used native hair samples at two mercury concentration ranges (0.20-0.71 and 0.80-1.63) per exercise. The results revealed relative standard deviations of 7.87-13.55% and 4.04-11.31% for the low and high mercury concentration ranges, respectively. A total of 16 out of 18 participating laboratories the QAP requirements and were allowed to analyze samples from the DEMOCOPHES pilot study. Web conferences after each ICI/EQUAS revealed this to be a new and effective tool for improving analytical performance and increasing capacity building. The procedure developed and tested in COPHES/DEMOCOPHES would be optimal for application on a global scale as regards implementation of the Minamata Convention on Mercury.

LEAD INTOXICATION EPIDEMIC CAUSED BY INGESTION OF CONTAMINATED GROUND PAPRIKA

OBJECTIVE Report of a lead intoxication epidemic caused by ingestion of contaminated ground paprika. DESIGN Retrospective study of case histories. SETTING Institutional, toxicological and medical referral center for ambulatory and hospitalized care. PATIENTS One hundred forty-one adults consumed paprika contaminated with lead tetroxide (red lead). INTERVENTIONS Intravenous calcium disodium versenate (edetic acid). MAIN OUTCOME MEASURES Measurement of zinc protoporphyrin:heme ratio of whole blood and the blood lead level. EDTA mobilization test. RESULTS Fifty-three patients had symptoms and signs of lead poisoning. The most common clinical signs were colic and/or anemia. Twenty-six persons showed increased lead absorption without clinical symptoms and signs. Chelation therapy with calcium disodium versenate resulted in complete clinical recovery. CONCLUSION Lead-contaminated ground paprika, not previously described as a cause of alimentary lead intoxication, may cause symptomatic poisoning.

Uptake and distribution of Cd in the ovaries, adrenals, and pituitary in pseudopregnant rats: effect of Cd on progesterone serum levels.

Pseudopregnant (PSP) rats were treated with 3.5 or 7.0 mg/kg body wt of CdCl2 on Day 1 of PSP sc. In the lower dose Cd content of the ovaries (luteal and nonluteal tissues), adrenals, pituitary, and blood on Days 1, 2, 5, 8, 10, and 12, and in the higher dose that of luteal and nonluteal tissue on Days 2 and 5 of PSP were determined with atomic absorption spectrophotometry. A rapid incorporation into the corpora lutea was measured on Day 1 and Day 2 of PSP followed by a decrease of Cd content toward the end of PSP whereas the nonluteal tissue, adrenals, and pituitary accumulated Cd gradually until the fifth to 10th day, respectively. Progesterone (P) serum levels were measured with RIA in the blood collected daily from the jugular vein following administration of 3.5 to 7.0 mg/kg body wt of CdCl2 sc on Day 1 or Day 8 of PSP. The serum levels of P remained unchanged when CdCl2 was administered on Day 1 of PSP; however, 7.0 mg/kg body wt CdCl2 given on Day 8 of PSP induced a significant decrease in serum levels of P. It is supposed that the regressing luteal tissue is more sensitive to the toxic effects of Cd than the developing one.

Effects of cobalt sulfate on prenatal development of mice, rats, and rabbits, and on early postnatal development of rats

The effects of cobalt sulfate administered to pregnant C57Bl mice, OFA-SD rats, and New Zealand rabbits was studied on fetal and postnatal offspring. Cobalt concentration in the maternal blood was increased in proportion to the administered doses. Cobalt crossed the placenta and appeared in the fetal blood and amniotic fluid. Regardless of the administered dose of cobalt sulfate, cobalt concentration in the blood peaked 2 h after administration. Cobalt produced dose-dependent maternal toxicity and was found to be embryotoxic in all three species, as evidenced by elevated frequency of fetuses with body weight or skeletal retardation and embryolethality. Cobalt increased the frequency of major anomalies significantly in mice and rats, with anomalies of the eyes, kidneys, skull, spine, and sternum in mice, and anomalies of the urogenital system in rats. Cobalt sulfate was not teratogenic in rabbits. Intra-amnial administration of cobalt sulfate produced a dose-dependent increase of the frequency of dead fetuses, and weight retardation of the live fetuses. The direct cytotoxic effect probably plays a role in the embryotoxic and teratogenic effects of cobalt. The postnatal examinations revealed a decrease of the perinatal index in the treated group. The body weight of the pups in the treated group was lower during wk 1 of life, but no difference was found between the control and treated by the end of wk 2. Eye opening was completed in the usual time period in both groups, while time of appearance of the teeth, descending of the testes, shaping of ears, and development of hearing was delayed in the treated group. The development of muscle strength and of the locomotor system was delayed. All the functions studied (forward movement, swimming, righting reflex) normalized by postnatal d 21, with the exception of muscle strength. It was concluded that cobalt sulfate exposure decreases the perinatal viability of the fetuses, but the functions of the surviving fetuses with perinatal retardation become compensated by postnatal wk 2-3. The development of fetuses is undisturbed thereafter.

Altered ovarian progesterone secretion induced by cadmium fails to interfere with embryo transport in the oviduct of the rat

The effect of Cadmium (Cd) on embryo transport through the oviduct and on ovarian progesterone (P) secretion were studied in the rat. Animals were given 2.5, 5, 10 mg/kg CdCl2 or 1.0 mL/kg NaCl sc on day 1 of pregnancy. On days 1, 2, 3, 4, and 5, they were anesthetized with pentobarbital, cannulae were inserted in one of the utero-ovarian veins, and 5-minute blood samples were taken from the ovary. Ovarian venous outflow was recorded, P was determined from the blood fractions, and secretion rates were calculated. P levels were determined in peripheral blood. Body weights and the wet weight of adrenals, ovaries, and oviducts were checked; oviducts and uterine horns were flushed; and number, location, and developmental stage of embryos were observed. Cd content of the oviducts was measured. Cd accumulated dose and time dependently in oviducts and induced a dose-dependent depression and delay in the rise of ovarian P secretion during days 1 through 5 of pregnancy. In the peripheral blood, P levels also failed to rise until day 4 of pregnancy in Cd-treated rats. In embryo transfer, however, no alteration could be observed. It is hypothesized that lack of vascular contact in the oviduct makes it possible for the preimplantation embryos to escape toxic effects of Cd.

Follow-up biological and genotoxicological monitoring of acrylonitrile- and dimethylformamide-exposed viscose rayon plant workers

In order to investigate the genotoxic effects of occupational acrylonitrile (ACN) and dimethylformamide (DMF) exposures, clinical serum and urine parameters and genotoxicological endpoints such as chromosome aberration (CA), sister chromatid exchange (SCE), high frequency SCE (HFC), cell cycle kinetics, and UV‐induced unscheduled DNA synthesis (UDS) were followed up three times during a 20‐month period in peripheral blood lymphocytes (PBL) of 26 workers (13 maintainers and 13 fiber producers) occupationally exposed to ANC and/or DMF in a viscose rayon plant, 26 matched control subjects, and six industrial controls (all males). Six of the 26 exposed subjects were hospitalized because of liver dysfunction that had developed due to inhalative DMF exposure. The rate of smoking was estimated on the basis of serum thiocyanate (SCN) levels. Average peak air ACN and DMF concentrations were over the maximum concentration limits at the time of both investigations. Urine ACN and monomethyl‐formamide (MMF) excretions of the exposed subjects were almost doubled after work shifts. An increase in lymphocyte count (in months 0 and 7), and severe alterations in the liver function were observed in the exposed subjects. In PBLs the proliferative rate index (PRI) was already increased in month 0 compared with the controls. In each study, significant increases in CA and SCE frequencies, as well as increases in UDS were found in PBLs of the exposed subjects. The frequencies of chromatid breaks and acentric fragments further increased in month 7 and remained constantly elevated in month 20. Increased yields of both chromatid and chromosome‐type exchange aberrations first appeared in month 20, when HFCs were 2.72 times more frequent in fiber producers than in maintainers. The role of some important biological confounding factors (age, white blood cell count, and hematocrit) and lifestyle confounding factors (smoking and drinking habits) were subjected to an analysis of variance during the second study. Increased CA, SCE, and UDS were found both in control and exposed smokers when current smoking was established on the basis of the serum SCN levels. The cytogenetic data suggest that occupational exposures to ACN and DMF induce considerable genotoxic consequences and may increase the cancer risk in the exposed human populations. Environ. Mol. Mutagen. 31:301–310, 1998

Embryotoxic and teratogenic effects of indium chloride in rats and rabbits.

Daily indium chloride doses of control (0), 50, 100, 200, or 400 mg/kg were administered orally to Sprague-Dawley rats by gavage, on d 6-15 of gestation, and daily metal doses of control (0), 50, 100, or 200 mg/kg were administered to New Zealand rabbits on d 6-20 of gestation. Further groups of pregnant rats were treated with control (0) or 400 mg/kg indium chloride orally on one of d 8, 9, 10, 11, 12, 13, 14, or 15 of gestation. The dams and fetuses were examined on d 21 (rats) and 30 (rabbits) of gestation, using standard teratological methods. Indium concentration was determined in the maternal and fetal blood, as well as in the amniotic fluid, by atomic absorption spectrometry. Indium was found to cross the placenta and appeared in fetal blood in proportion to the metal concentration of the maternal blood. In the amniotic fluid, indium concentrations remained below the detection limit. In rats, indium chloride produced dose-dependent maternal toxic effects, with a dose of 400 mg/kg inducing embryotoxicity (embryolethality) and teratogenicity. Doses of 200 and 100 mg/kg were embryotoxic (retarding) and teratogenic, causing skeletal and visceral anomalies in addition to external anomalies (rudimentary or missing tail, syndactylia, clubfoot, exencephalia) in rats. In rabbits, 200 mg/kg indium chloride was lethal for the dams and the embryos (some of the animals died, and the number of abortions and full resorptions increased). This dose was found to be teratogenic (caused gross renal anomalies) and increased the frequency of fetuses with skeletal retardation. In rats, the effects of indium chloride causing fetal retardation was found to be independent of exposure time. The teratogenic effects were the highest on d 11 and 12 of gestation, when indium chloride caused gross external malformations. Data suggest that the teratogenic effects of indium chloride can be attributed primarily to a direct cytotoxic action of indium resulting from placental transfer, but the effect is not a selective one, as it appears only in the presence of maternal toxic effects.Daily indium chloride doses of control (0), 50, 100, 200, or 400 mg/kg were administered orally to Sprague-Dawley rats by gavage, on d 6-15 of gestation, and daily metal doses of control (0), 50, 100, or 200 mg/kg were administered to New Zealand rabbits on d 6-20 of gestation. Further groups of pregnant rats were treated with control (0) or 400 mg/kg indium chloride orally on one of d 8, 9, 10, 11, 12, 13, 14, or 15 of gestation. The dams and fetuses were examined on d 21 (rats) and 30 (rabbits) of gestation, using standard teratological methods. Indium concentration was determined in the maternal and fetal blood, as well as in the amniotic fluid, by atomic absorption spectrometry. Indium was found to cross the placenta and appeared in fetal blood in proportion to the metal concentration of the maternal blood. In the amniotic fluid, indium concentrations remained below the detection limit. In rats, indium chloride produced dose-dependent maternal toxic effects, with a dose of 400 mg/kg inducing embryotoxicity (embryolethality) and teratogenicity. Doses of 200 and 100 mg/kg were embryotoxic (retarding) and teratogenic, causing skeletal and visceral anomalies in addition to external anomalies (rudimentary or missing tail, syndactylia, clubfoot, exencephalia) in rats. In rabbits, 200 mg/kg indium chloride was lethal for the dams and the embryos (some of the animals died, and the number of abortions and full resorptions increased). This dose was found to be teratogenic (caused gross renal anomalies) and increased the frequency of fetuses with skeletal retardation. In rats, the effects of indium chloride causing fetal retardation was found to be independent of exposure time. The teratogenic effects were the highest on d 11 and 12 of gestation, when indium chloride caused gross external malformations. Data suggest that the teratogenic effects of indium chloride can be attributed primarily to a direct cytotoxic action of indium resulting from placental transfer, but the effect is not a selective one, as it appears only in the presence of maternal toxic effects.

Case study: Possible differences in phthalates exposure among the Czech, Hungarian, and Slovak populations identified based on the DEMOCOPHES pilot study results

OBJECTIVE Phthalates and their metabolites are classified as endocrine modulators. They affect the hormonal balance in both children and adults. The aim of this publication was to compare the urinary levels of phthalate metabolites in selected populations of the Czech Republic (CZ), Slovakia (SK), and Hungary (HU) in relation to the sources of phthalate exposure identified by means of questionnaire (personal care products, floor and wall coverings, plastic toys, and some kinds of foods). METHODS Data were obtained through the twin projects COPHES (COnsortium to Perform Human biomonitoring on a European Scale) and DEMOCOPHES (DEMOnstration of a study to COordinate and Perform Human biomonitoring on a European Scale) from 2009 to 2012. The target groups were children aged 6-11 years old and their mothers up to 45 years of age. The metabolites of phthalates (monomethyl phthalate (MMP), monoethyl phthalate (MEP), monobenzyl phthalate (MBzP), mono-cyclohexyl phthalate (MCHP), mono-(2-ethylhexyl) phthalate (MEHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (5OH-MEHP), and mono-(2-ethyl-5-oxohexyl) phthalate (5OXO-MEHP)) were analysed in first morning urine samples. After enzymatic glucuronide cleavage, the urine sample analyses were performed using ultra-high-performance liquid chromatography-electrospray ionization tandem mass spectrometry (UHPLC-ESI-MS/MS) in one laboratory that qualified in the External Quality Assessment exercises organised by COPHES. RESULTS Significant differences in phthalate exposure between countries were revealed for children only but not for mothers. The concentrations of 5-OH-MEHP (P<0.001), 5OXO-MEHP (P<0.001), and their sum (P<0.001) were the highest in SK compared to CZ and HU. The health based guidance values for the sum of DEHP metabolites 5-OH MEHP and 5OXO-MEHP established by the German Commission for biomonitoring of 300 µg/L and 500 µg/L for women adults and children, respectively, were only exceeded in one mother and three boys. A significant difference was also found for MEP (P=0.0149), with the highest concentrations detected in HU. In all countries, the increasing frequency of using personal care products significantly elevated the concentrations of MEP. CONCLUSION Some differences were observed between countries in the concentrations of individual urinary phthalate metabolites in children. However, the questionnaire results give no direct explanation for the differences between the countries except the variation in using personal care products.