| 1. |
- Ekman, Eva, et al.
(författare)
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Determination of 5-hydroxythiabendazole in human urine as a biomarker of exposure to thiabendazole using LC/MS/MS.
- 2014
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Ingår i: Journal of Chromatography. B. - : Elsevier BV. - 1873-376X .- 1570-0232. ; 973, s. 61-67
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Tidskriftsartikel (refereegranskat)abstract
- Thiabendazole (TBZ) is widely used as a pre-planting and post-harvest agricultural fungicide and as an anthelminthic in humans and animals. TBZ is of toxicological concern, since adverse effects including nephrogenic, hepatogenic, teratogenic and neurological effects have been reported in mammals. Occupational exposure can occur among agricultural workers and the general public may be environmentally exposed to TBZ through the diet. The metabolite 5-hydroxythiabendazole (5-OH-TBZ) was chosen as biomarker of exposure to TBZ and a LC/MS/MS method for the quantification of 5-OH-TBZ in human urine was developed. The method includes enzyme hydrolysis, as 5-OH-TBZ is conjugated to glucuronide and sulphate in urine. Sample through put was optimised using 96-well plates for sample handling as well as for solid phase extraction (SPE). The method has excellent, within-run, between-run and between-batch precision between 4 and 9%. The limit of detection (LOD) of 0.05 and a limit of quantification (LOQ) of 0.13ng 5-OH-TBZ/mL urine enable detection in environmentally exposed populations. When applying the method in a general Swedish population, 52% had levels above LOD. The method was also applied in one oral and one dermal human experimental exposure study in two individuals. After oral exposure, the excretion of 5-OH-TBZ in urine was described by a two-compartment model and both the first rapid and the second slower elimination phase followed first-order kinetics, with estimated elimination half-life of 2h and 9-12h. The recoveries in urine were between 21 and 24% of the dose. Dermal exposure was described by a one compartment model and followed first order kinetics, with estimated elimination half-life of 9-18h. The recovery in urine was 1% of the administrated dose of TBZ. Although these studies are limited to two individuals, the data provide new basic information regarding the toxicokinetics of TBZ after oral and dermal exposure.
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| 2. |
- Faniband, Moosa, et al.
(författare)
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Human biological monitoring of suspected endocrine-disrupting compounds.
- 2014
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Ingår i: Asian Journal of Andrology. - 1008-682X. ; 16:1, s. 5-16
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Forskningsöversikt (refereegranskat)abstract
- Endocrine-disrupting compounds are exogenous agents that interfere with the natural hormones of the body. Human biological monitoring is a powerful method for monitoring exposure to endocrine disrupting compounds. In this review, we describe human biological monitoring systems for different groups of endocrine disrupting compounds, polychlorinated biphenyls, brominated flame retardants, phthalates, alkylphenols, pesticides, metals, perfluronated compounds, parabens, ultraviolet filters, and organic solvents. The aspects discussed are origin to exposure, metabolism, matrices to analyse, analytical determination methods, determinants, and time trends.
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| 3. |
- van Wendel de Joode, Berna, et al.
(författare)
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Aerial Application of Mancozeb and Urinary Ethylene Thiourea (ETU) Concentrations among Pregnant Women in Costa Rica: The Infants' Environmental Health Study (ISA).
- 2014
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Ingår i: Environmental Health Perspectives. - : Environmental Health Perspectives. - 1552-9924 .- 0091-6765. ; 122:12, s. 1321-1328
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Tidskriftsartikel (refereegranskat)abstract
- Background: Mancozeb and its main metabolite ethylene thiourea (ETU) may alter thyroid function; thyroid hormones are essential for fetal brain development. In Costa Rica, mancozeb is aerially sprayed at large-scale banana plantations on a weekly basis. Objectives: (1) evaluate urinary ETU concentrations in pregnant women living nearby large-scale banana plantations; (2) compare their estimated daily intake (EDI) with established Reference Doses (RfDs); and (3) identify factors that predict their urinary ETU concentrations. Methods: We enrolled 451 pregnant women from Matina County, Costa Rica, with large-scale banana production. We visited 445 women up to three times during pregnancy to obtain urine samples (n = 872) and information on factors that possibly influence exposure. We determined urinary ETU concentrations using liquid chromatography mass spectrometry (LCMS). Results: Pregnant women's median urinary ETU concentrations were more than five times higher than reported for other general populations. Seventy-two percent of the women had EDIs above the RfD. Women who lived closest (1st quartile, < 48 meters) to banana plantations on average had a 45% (95% CI: 23, 72%) higher urinary ETU compared with women who lived farthest away (4th quartile, ≥ 565 meter). Compared with the other women, ETU was also higher in women who washed agricultural work clothes on day before sampling (11%; 95% CI; 4.9, 17%), worked in agriculture during pregnancy (19%; 95% CI: 9.3, 29), and immigrant women (6.2%; 95% CI: 1.0, 13%). Conclusions: The pregnant women's urinary ETU concentrations are of concern, and the principal source of exposure is likely to be aerial spraying of mancozeb. The factors predicting ETU provide insight into possibilities for exposure reduction.
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