Journal of toxicology and environmental health最新文献

{"title":"Comparison of the effects of various fine particles on IgE antibody production in mice inhaling Japanese cedar pollen allergens.","authors":"K Maejima,&nbsp;K Tamura,&nbsp;Y Taniguchi,&nbsp;S Nagase,&nbsp;H Tanaka","doi":"10.1080/00984109708984062","DOIUrl":"https://doi.org/10.1080/00984109708984062","url":null,"abstract":"<p><p>The adjuvant effects of various fine particles [Kanto loam dust, fly ash, carbon black, diesel exhaust particles (DEP), and aluminum hydroxide (alum)] on immunoglobulin E (IgE) antibody production in female BDF1 mice were examined. In experiment 1, animals both received 25 micrograms of each particle intranasally and were exposed to aerosolized Japanese cedar pollen allergens (JCPA) for 30 min/d at 1-wk intervals for the first 8 wk. This was followed by exposure for 30 min every 3 wk for the next 9 wk. As parameters of allergic rhinitis, measurements were made of JCPA-specific IgE and IgG antibody titers, the protein-adsorbing capacity of each type of particle, and nasal rubbing movements. The increases in anti-JCPA IgE and IgG antibody production in mice treated with aerosolized JCPA plus respective particles were significantly greater than that found with aerosolized JCPA alone. This was associated with no marked differences in the other allergic rhinitis parameters. In experiment 2, after the administration of particles as in experiment 1, about 160,000 grains of Japanese cedar pollen (JCP, native dry pollen) were dropped onto the tip of the nose of mice twice a week for 16 wk. Six weeks after the first immunization, the anti-JCPA IgE antibody titers of groups treated with the respective particles were greater than 1:20, whereas those of mice treated with JCP alone were 1:10. No significant differences in the anti-JCPA IgE and IgG antibody productions, nasal rubbing counts, or histopathological changes were observed after 18 wk. These results suggested the nature of the particles, their capacity to adsorb antigens, and/or their size may not be related to enhancement of IgG antibody production nor symptoms of allergic rhinitis. However, IgE antibody production seemed to occur earlier in mice treated with particles than in mice immunized with allergens alone.</p>","PeriodicalId":17524,"journal":{"name":"Journal of toxicology and environmental health","volume":"52 3","pages":"231-48"},"PeriodicalIF":0.0,"publicationDate":"1997-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00984109708984062","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20255880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pharmacodynamic model of the rat estrus cycle in relation to endocrine disruptors.","authors":"M E Andersen,&nbsp;H J Clewell,&nbsp;J Gearhart,&nbsp;B C Allen,&nbsp;H A Barton","doi":"10.1080/00984109708984060","DOIUrl":"https://doi.org/10.1080/00984109708984060","url":null,"abstract":"<p><p>Several strains of laboratory rats have a high background incidence of mammary tumors and develop a persistent, anovulatory estrus condition at about 12 mo of age. The increased tumor incidence is believed to be associated with elevated estradiol (E2) and prolactin during the period of persistent estrus. A pharmacodynamic estrus cycle (PD-EC) model for the Sprague-Dawley rats has been developed in an attempt to analyze the physiological basis of early-onset persistent estrus and to examine the potential sites of interactions in the hypothalamic-pituitary-ovarian axis for endocrine-modulating xenobiotics that accelerate the onset of persistent estrus. This initial estrus cycle model focused solely on cyclical changes in E2 and luteinizing hormone (LH). An LH surge was scheduled when a hypothetical estrus cycle-related protein (EC-RP) under transcriptional control by the E2 receptor reached a critical concentration. In the model, aging-related cumulative hypothalamic E2 exposure impaired the LH surge by reducing the rate of production of the EC-RP. The progressively decreasing intercycle resynthesis rate leads first to longer, variable-length cycles and finally to persistent estrus at about 12 mo of age. This model construct is consistent with early-onset persistent estrus related to neonatal E2 exposures, with acyclicity associated with high-dose E2 exposure in the adult, and with persistent estrus conditions associated with exposures to xenobiotic endocrine modulators that are either weak E2 antagonists or weak E2 agonists. With further development these pharmacodynamic estrus cycle models should be useful in aiding risk assessments for compounds causing mammary-tissue tumors associated with persistent estrus states.</p>","PeriodicalId":17524,"journal":{"name":"Journal of toxicology and environmental health","volume":"52 3","pages":"189-209"},"PeriodicalIF":0.0,"publicationDate":"1997-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00984109708984060","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20255944","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Percutaneous permeation of N,N-diethyl-m-toluamide (DEET) from commercial mosquito repellents and the effect of solvent.","authors":"J Stinecipher,&nbsp;J Shah","doi":"10.1080/00984109708984056","DOIUrl":"https://doi.org/10.1080/00984109708984056","url":null,"abstract":"<p><p>N,N-Diethyl-m-toluamide (DEET), the active ingredient in many commercial mosquito repellents, is thought to be responsible for a wide range of local and systemic adverse reactions following its use. Many investigators have studied the dermal absorption of pure DEET; however, there is only one report in the literature on the absorption of DEET from commercial mosquito repellents and the effect of concentration of DEET on its absorption through skin. The first objective of the present study was to evaluate the permeation characteristics of DEET from four commercial products, Everglades (95%), Repel Deerhunters (52.25%), Off Skintastic (6.65%), and Skedaddle (6.2%), as compared to pure DEET (approximately 100%). The second objective was to study the effects of ethanol, the solvent for DEET, on the permeation of DEET and investigate its potential for enhancing the dermal absorption of DEET. Permeation studies of DEET from commercial mosquito repellents and from solutions containing various percentages of ethanol were conducted across human skin using an infinite dose technique with a Franz diffusion cell. Permeation parameters such as steady-state flux (Jss), lag time (tL), diffusion coefficient (D), permeability (P), and skin/ vehicle partition coefficient (K) were obtained from the permeation profiles in each case. The cumulative amount of DEET permeated can be ranked according to the following order: neat DEET (100%) = Everglades (95%) > Repel (52.25%) > Skedaddle (6.2%) = Off Skintastic (6.65%). Pure DEET exhibited the highest flux value of 63.20 +/- 24.52 micrograms/cm2-h, while Off Skintastic had the lowest value of 21.12 +/- 14.75 micrograms/cm2-h. The tL and D values for each of the products were similar to that of pure DEET. The total amount of DEET permeated from 30-45% ethanolic solutions at the end of 36 h was significantly higher than that from pure DEET and from the 60-90% ethanolic solutions. The Jss, P, and K values of DEET from the 30-45% ethanolic solutions were significantly higher than those from the 75-90% ethanolic solutions, while the tL and D values were similar for each solution. Therefore, there is potential for significant absorption of DEET after the dermal application of commercial mosquito repellents, and ethanol, used as a solvent, may enhance the permeation of DEET.</p>","PeriodicalId":17524,"journal":{"name":"Journal of toxicology and environmental health","volume":"52 2","pages":"119-35"},"PeriodicalIF":0.0,"publicationDate":"1997-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00984109708984056","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20250079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cadmium-induced apoptosis in the urogenital organs of the male rat and its suppression by chelation.","authors":"H Yan,&nbsp;C E Carter,&nbsp;C Xu,&nbsp;P K Singh,&nbsp;M M Jones,&nbsp;J E Johnson,&nbsp;M S Dietrich","doi":"10.1080/00984109708984058","DOIUrl":"https://doi.org/10.1080/00984109708984058","url":null,"abstract":"<p><p>Cadmium-induced apoptosis is shown to occur, in vivo, in several organs of the male Wistar rat urogenital system, 48 h after cadmium administration i.p. at a dose of 0.03 mmol/kg. Characteristic DNA fragmentation (as measured by an enzyme-linked immunosorbent-assay, ELISA) and histopathologically observed changes characteristic of apoptosis are found in the kidney, prostate, seminal vesicles, testes, and epididymis. TUNEL assay also demonstrates the apoptosis. Such changes are absent from bladder and vas deferens tissue. Timely administration of an appropriate chelating agent capable of reaching intracellular cadmium binding sites can suppress the processes leading to apoptosis. Administration of monoisomyl meso-2,3-dimercaptosuccinate (Mi-ADMS, 0.5 mmol/kg i.p.) to cadmium-treated rats is effective in greatly reducing typical histopathologic signs of apoptosis and the associated chromatin DNA fragmentation as revealed by ELISA when the antagonist is administered 1 h after cadmium. Administration of the chelating agent at law times results in greater degradation of DNA into oligonucleotides and more prominent histopathological evidence of apoptotic changes in the affected organs of the rat urogenital system. There is also a progressive increase in apoptotic changes indicated by TUNEL assay, as the antagonist is administered at progressively greater intervals after cadmium.</p>","PeriodicalId":17524,"journal":{"name":"Journal of toxicology and environmental health","volume":"52 2","pages":"149-68"},"PeriodicalIF":0.0,"publicationDate":"1997-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00984109708984058","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20250081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Roles of DT diaphorase in the genotoxicity of nitroaromatic compounds in human and fish cell lines.","authors":"B M Hasspieler,&nbsp;G D Haffner,&nbsp;K Adeli","doi":"10.1080/00984109708984057","DOIUrl":"https://doi.org/10.1080/00984109708984057","url":null,"abstract":"<p><p>The genotoxicity of nitroaromatic compounds was examined in two cultured cell lines, namely, a human hepatoma cell line, HepG2, and a brown bullhead fibroblast cell line, BB. Furthermore, the role of the quinone-reducing enzyme DT diaphorase [NAD(P)H:(quinone acceptor) oxidoreductase] was examined with respect to its influence on the genotoxic effects of model nitroaromatic pollutants. The nitroreductive characteristics of these two cell lines were examined using an acetylated cytochrome c reduction assay for enzymatic nitroreductase activity. Subsequently, the influence of DT diaphorase on the genotoxicity of two model nitroaromatics, 4-nitroquinoline 1-oxide (4NQ) and nitrofurantoin (NF), revealed that DT diaphorase was the predominant 4NQ reductase in cytosols of both cell lines, but played a lesser role in NF reduction in both species. Despite these interspecific similarities, results revealed marked qualitative differences between the two species in terms of the influence of DT diaphorase on quinone-mediated genotoxicity. When pretreated with the DT diaphorase inhibitor dicoumarol, HepG2 cells exhibited an exacerbation of genotoxicity in the presence of 4NQ, indicating a protective influence of the enzyme. In contrast, 4NQ genotoxicity in BB cells was reduced in the presence of dicoumarol, indicating a deleterious effect of DT diaphorase activity. Conversely, dicoumarol pretreatment was moderately protective against NF-mediated genotoxicity in HepG2 cells but exacerbated NF toxicity in BB cells. This study illustrates the manner in which functionally analogous enzymes may have markedly distinct influences on xenobiotic toxicity in different cellular systems.</p>","PeriodicalId":17524,"journal":{"name":"Journal of toxicology and environmental health","volume":"52 2","pages":"137-48"},"PeriodicalIF":0.0,"publicationDate":"1997-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00984109708984057","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20250080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of hyperthyroidism on the in vitro metabolism and covalent binding of 1,1-dichloroethylene in rat liver microsomes.","authors":"G H Gunasena,&nbsp;M F Kanz","doi":"10.1080/00984109708984059","DOIUrl":"https://doi.org/10.1080/00984109708984059","url":null,"abstract":"<p><p>Hyperthyroidism potentiates the in vivo hepatotoxicity of 1,1-dicholoroethylene (DCE) in rats, with a concomitant increase in [14C]-DCE covalent binding. The enhanced injury produced in hyperthyroid livers by DCE could be due to alterations in either the bioactivation or detoxication phases of DCE metabolism. Previous in vitro studies suggested that hyperthyroidism did not potentiate DCE hepatotoxicity by increasing DCE oxidation to intermediates which were able to covalently bind. Several factors, however, that could contribute to the magnitude of DCE bioactivation or covalent binding were not examined. Our objectives were to characterize the effects of hyperthyroidism in male Sprague-Dawley rats on: (1) covalent binding of [14C]-DCE to microsomes and other subcellular fractions, (2) microsomal mixed-function oxidase (MFO) and glutathione S-transferase (GST) activities, and (3) inactivation of microsomal enzyme activities by presumptive DCE reactive intermediates. Hyperthyroid (HYPERT) and euthyroid (EUT) rats received 3 s.c. injections of thyroxine (100 micrograms/100 g) or vehicle, respectively, at 48-h intervals; microsomes and other subcellular fractions were isolated from HYPERT and EUT livers 24 h after the last injection. [14C]-DCE-derived covalent binding was consistently greater in EUT than HYPERT microsomes. The absence of NADH, and the addition of low concentrations (0.1 and 0.5 mM), but not higher concentrations (> 1 mM), of glutathione (GSH) diminished covalent binding to a greater extent in HYPERT than EUT microsomes. Covalent binding in mitochondrial, nuclear, and cytosolic fractions of EUT and HYPERT livers was equivalent. Regression analysis of covalent binding to liver cell fractions from both EUT and HYPERT rats showed a significant correlation with P-450 content. Hyperthyroidism decreased microsomal, but not mitochondrial, cytochrome P-450 content, and MFO activities for 7-ethoxycoumarin and benzphermine were similarly decreased. Hyperthyroidism also diminished microsomal GST activity, and altered GST kinetics for both GSH and 1-chloro-2,4-dinitrobenzene (CDNB). The magnitude of inactivation of MFO and GST activities in the presence of DCE (presumably by DCE reactive intermediates) was comparable between EUT and HYPERT microsomes. When covalent binding was standardized to cytochrome P-450 concentrations in microsomes and mitochondria, HYPERT fractions exhibited slightly greater covalent binding than EUT fractions, suggesting that hyperthyroidism does not reduce the capacity of P-450 hemoproteins to bioactive DCE. Thus, potentiation of DCE hepatotoxicity by hyperthyroidism may be predominantly due to diminished Phase II constituents, and major increases in reactive intermediate/conjugates that covalently bind to and impair critical cellular molecules.</p>","PeriodicalId":17524,"journal":{"name":"Journal of toxicology and environmental health","volume":"52 2","pages":"169-88"},"PeriodicalIF":0.0,"publicationDate":"1997-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00984109708984059","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20250669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preliminary assessment of PCB risks to human and ecological health in the lower Passaic River.","authors":"B L Finley,&nbsp;K R Trowbridge,&nbsp;S Burton,&nbsp;D M Proctor,&nbsp;J M Panko,&nbsp;D J Paustenbach","doi":"10.1080/00984109708984055","DOIUrl":"https://doi.org/10.1080/00984109708984055","url":null,"abstract":"<p><p>Concentrations of Aroclor mixtures and specific polychlorinated biphenyl (PCB) congeners were measured in surface sediments and aquatic biota (striped bass fillet, mummichog, and blue crab muscle and hepatopancreas) collected from the lower Passaic River. Several of the 47 surface sediment samples contained Aroclor concentrations that exceeded a National Oceanic and Atmospheric Administration (NOAA) benchmark level for \"total PCBs\" (22.7 micrograms/kg). Each of the 18 PCB congeners analyzed in aquatic biota was detected in one or more tissue samples, and numerous congeners were detected in every sample (IUPAC numbers 77, 105, 114, 118, 123, 126, 156, 157, 167, and 189). PCB congener concentrations were similar to those that have been reported in fish from other waterways that contain elevated levels of PCBs. Congener 118 was present at the highest concentration in almost all samples, and constituted 14-60% of the total PCB mass (sum of all congener masses) measured in any given tissue sample. In spite of the prevalence of PCB congeners in biota tissues (up to 1314 micrograms/kg total PCBs), Aroclors were not detected in bass or crab samples at a limit of detection of 33-55 micrograms/kg. This anomaly may be due to selective degradation of certain PCB congeners that are used to analytically recognize and quantitate Aroclors. Using the measured sediment concentrations, a food web model accurately predicted blue crab muscle concentrations of individual PCB congeners (typically within a factor of two) and was also fairly accurate for mummichog (typically within an order of magnitude). Concentrations in striped bass fillet were underestimated by factors of approximately 20-140. Increased cancer risk estimates associated with fish and crab consumption were obtained using four different methods. Using Aroclor tissue concentrations (one-half the limit of detection) and an Aroclor slope factor, total risks were 2.6 x 10(-6); using the \"total PCB\" measurements and an Aroclor slope factor, total risks were 1.9 x 10(-5); the \"PCB-TEQ\" method yielded total risks of 6.5 x 10(-4); and USEPA's recent suggested approach for evaluating \"dioxin-like\" and non-\"dioxin-like\" effects resulted in a total risk of 6.6 x 10(-4). This wide range in risk estimates indicates that it is critical to the risk management decision-making process that data requirements and risk assessment objectives be carefully evaluated early in the investigation process.</p>","PeriodicalId":17524,"journal":{"name":"Journal of toxicology and environmental health","volume":"52 2","pages":"95-118"},"PeriodicalIF":0.0,"publicationDate":"1997-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00984109708984055","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20250078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Epidemiologic assessment of measures used to indicate low-level exposure to mercury vapor (Hg).","authors":"M E Cianciola,&nbsp;D Echeverria,&nbsp;M D Martin,&nbsp;H V Aposian,&nbsp;J S Woods","doi":"10.1080/00984109708984050","DOIUrl":"https://doi.org/10.1080/00984109708984050","url":null,"abstract":"<p><p>Mercury (Hg) concentrations in individual spot urine samples collected over consecutive 1-d periods were compared with Hg concentrations measured in combined 24-h urine samples from 69 practicing dental professionals with low exposure to Hg vapor (Hg) in order to validate the use of spot urine samples as an indicator of Hg exposure. The level of Hg in air as an exposure measure was also evaluated by comparing air concentrations of Hg in dental offices with both spot and 24-h urine Hg levels. The results showed: (1) There was little diurnal variation (approximately 9%) in urinary Hg values; (2) a strong correlation (R2 = .85) exists between the Hg concentration in the first morning void and that in a complete 24-h urine sample; (3) adjustment of urinary Hg levels for creatinine concentrations did not improve this correlation; (4) there was no added value in the speciation of total urinary Hg into the inorganic Hg fraction; and (5) concentrations of Hg in air did not significantly correlate with measures of Hg in urine at this low Hg exposure level. We conclude from this study that first morning void urine samples may be used to derive reasonably valid estimates of Hg concentrations found in the total amount of urine collected over a 24-h period. Thus, due to its comparability, ease of collection, and lower cost, the first morning urine void may be used in place of a sample collected over a full 24 h to facilitate Hg exposure assessments in epidemiologic studies that use urinary Hg levels as a measure of low-level Hg exposure.</p>","PeriodicalId":17524,"journal":{"name":"Journal of toxicology and environmental health","volume":"52 1","pages":"19-33"},"PeriodicalIF":0.0,"publicationDate":"1997-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00984109708984050","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20211903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Relationships between smoking habits, smoking-associated hematological changes, and urinary benzene metabolites.","authors":"V Haufroid,&nbsp;P Hotz,&nbsp;P Carbonnelle,&nbsp;R Lauwerys","doi":"10.1080/00984109708984049","DOIUrl":"https://doi.org/10.1080/00984109708984049","url":null,"abstract":"<p><p>It has been suggested that benzene metabolites might be good indicators of smoking. Moreover, benzene could stimulate the neutrophil lineage while depressing the lymphocytic and erythroid lineages, possibly by an interference with cytokines. The effect on the neutrophil lineage could explain the smokers' leukocytosis, the mechanism of which is presently unknown. Therefore, the usefulness of benzene metabolites as indicators of smoking was compared to that of cotinine and thiocyanate, and the relationships between benzene metabolites, the hematological parameters of smokers, and interleukin 1 alpha production were examined. The results show that benzene metabolites are not better indicators of smoking status than cotinine or thiocyanate. Furthermore, it seems unlikely that the smokers' leukocytosis is benzene induced.</p>","PeriodicalId":17524,"journal":{"name":"Journal of toxicology and environmental health","volume":"52 1","pages":"1-17"},"PeriodicalIF":0.0,"publicationDate":"1997-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00984109708984049","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20212011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Developmental toxicity of dermally applied crude oils in rats.","authors":"M H Feuston,&nbsp;C E Hamilton,&nbsp;C A Schreiner,&nbsp;C R Mackerer","doi":"10.1080/00984109708984054","DOIUrl":"https://doi.org/10.1080/00984109708984054","url":null,"abstract":"<p><p>Two crude oils, differing in viscosity (V) and nitrogen (N) and sulfur (S) content, were evaluated for pre- and postnatal developmental toxicity. In Crude I (low V, low N, low S) studies, the material was applied neat to the clipped backs of pregnant rats at dose levels of 0, 125, 500, 1000 (postnatal only), and 2000 (prenatal only) mg/kg. In Crude II (high V, high N, moderate S) studies, the oil was applied similarly but at dose levels of 0, 30, 125, and 500 mg/kg. Rats were exposed to the crude oils on gestation days (GD) 0-19; application sites were not covered. \"Prenatal\" rats were killed on GD 20. \"Postnatal\" rats were allowed to deliver naturally; surviving dams and litters were killed 3-4 wk postpartum. Both crude oils produced maternal and developmental toxicity. Adverse fetal effects included increased in utero death, decreased body weight, and reduced ossification of skeletal elements. Parturition was delayed in Crude II dams at 500 mg/kg. The 4-d viability index was decreased in all Crude II-exposed groups. Pup body weights were decreased by each oil, but at the high dose only. Prenatal effects are probably related to polynuclear aromatic compounds (PAC) found in petroleum. The cause(s) of delayed parturition and postnatal toxicity have not been determined.</p>","PeriodicalId":17524,"journal":{"name":"Journal of toxicology and environmental health","volume":"52 1","pages":"79-93"},"PeriodicalIF":0.0,"publicationDate":"1997-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00984109708984054","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20211907","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}