Document Lp7Vev1XqJoVdOqLLkEdz8ovX

Volume 53, No. 7 INDUSTRIAL HYGIENE DIGEST July 1989 lymphomas (NHL) were evaluated in a case-referent study encompassing 54 cases of HD, 106 cases of NHL, and 275 referents, all alive. Exposure in formation was obtained by questionnaires posted to the subjects. Crude rate ratios were increased for various occupational exposures, including sol vents, welding, wood preservatives, phenoxy acids, and fresh wood (sawmill workers, lumberjacks, paper pulp workers). After further analyses based on logistic regression occupational exposures to welding and creosote remained as significant risk factors for HD. For NHL, occupational exposures to solvents, phenoxy acids, and creosote but also work as carpenter or cabinet maker and contacts with pets (other than dogs, cats, and birds) were associated with significantly increased risks. --Authors' abstract 783/89 THE LEAD-EXPOSED WORKER D. Rempel, JAMA, 262(4):532-534, July 28, 1989. 19 refs. The lead standard established by the federal Occupational Safety and Health Administration in 1978 requires physicians and employers to follow very specific guidelines when treating leadexposed workers. For example, if a worker's blood lead level is 2.90 umoi/L of whole blood or greater, the worker must be removed from work, with full pay and retention of seniority, until the blood level falls below 1.95 pmol/L. Phy sicians play a key role in the implementation of the lead standard; the standard specifies fre quency of blood lead measurements, frequency and extent of medical monitoring, and medical removal from work. This article reviews the lead standard as it applies to physicians and makes recommen dations about managing the worker with lead poisoning. --Author's abstract 784/89 MUTUAL METABOLIC SUPPRESSION BETWEEN BENZENE AND TOLUENE IN MAN 0. Inoue, et al, International Arch. Occup. Environ. Health 60:15-20, 1988 The exposure intensity during a shift and the metabolite levels in the shift-end urine were examined in male workers exposed to either benzene (65 subjects; the benzene group), toluene (35 subjects; the toluene group), or a mixture of both (55 subjects; the mixture group). In addition, 35 non-exposed male workers (the control group) were similarly examined for urinary metabolites to define background levels. A linear relationship was established between the intensity of solvent exposure and the corresponding urinary metabolite levels (i .e. .phenol, catechol and quinol from benzene, and hippuric acid and o-cresol from toluene) in each case when one of the three exposed groups was combined with the control group for calculation. Comparison of regression lines in combination with regression analysis disclosed that urinary levels of phenol and quinol (but not catechol) were lower in the mixture group than in the benzene group when the intensities of exposure to benzene were comparable, indicating that the biotransformation of benzene to phenolic compounds (excluding catechol) in man is suppressed by co-exposure to toluene. Conversely, metabolisin ,of toluene to hippuric acid was suppressed by benzene co-exposure. Conversion of toluene to -cresol was also reduced by benzene, but to a lesser ex tent. The significance of the present findings on the mutual suppression of metabolism between benzene and toluene is discussed in relation to solvent toxicology and biological monitoring of exposure to the solvents. --Authors' abstract 785/89 STUDIES OF ACUTE NEPHROTOXIC POTENTIAL OF TRICHLOROETHYLENE IN FISCHER 344 RATS S. K. Chakrabarti and B. Tuchweber, J. Toxicol. Environ. Health 23:147-158, 1988 Group of male Fischer 344 rats, after pretreatment with phenobarbital (80 mg/kg, ip 3 d), were treated ip in corn oil with 0, 5.5, 11.0, and 22.0 mmol trichloroethylene (TRI) per kg body weight. Urines were collected 24 h after the treatment and the animals were then sacrificed. The nephro toxicity of TRI was then studied by measuring certain biochemical parameters characteristic of renal injury and its in vivo metabolism by quantitating the TRI principal urinary metabo lites. Treatment of rats with TRI up to 11 mmol/kg did not influence any of the measured biochemical .parameters of nephrotoxicity.^jQn the other hand. jiianl/icant..tncreffiTTn W'Hrlnary level of N-acetyr^?i^J-|i0[jiJdait and" glucose as..' dte- served at 24 Ht4'- level (22 mmol/kg) or TR4t: Urinary excretions of both trichloroethanol and trichloroacetic acid reached an apparent saturation at the highest dose level of TRI. In inhalation studies, urinary levels of r-glutamyltranspeptidase, NAG, glucose, proteins, and serum urea nitrogen were significantly in creased at 24 h when rats were exposed to either 1000 or 2000 ppm TRI for 6 h. The capacity of renal cortical slices to accumulate p-amino- hippurate was significantly reduced 24 h after the exposure to 22 naal. TRl/kp (ipl. or to 1000 or 2000 ppm TRI. These demonstrated that TRI exerts Its ieut$/ 'C poteatial at a very high dose^m}*, ihrotoxic insult -------' * slhiy glome^r.TM*! exposed by fnhaf ther z These data further. ./4*d' of a capacity*!t*Ltd. the express i on of acute nephrotexii "`fti Ft'scher 344 rats. --Authors' abstract 19 SL 034859