Documents toluene 22 results

"Objectives This study determined whether performance in neurobehavioral tests deteriorates during subjectively annoying chemical challenge below known neurotoxic thresholds among persons with toxic encephalopathy with subjective hypersensitivity to chemicals.Methods Subjects with symptoms and previous neuropsychological test results compatible with toxic encephalopathy (TE) of either type 2A (N=12) or 2B (N=12) and unexposed referents (N=12) were challenged in an exposure chamber. In a counterbalanced design, the subjects were exposed on 2 occasions to increasing air concentrations of n-butyl acetate and toluene at levels well below the thresholds for neurotoxic effects. Attention and motor speed tests were given (i) in room air outside the chamber before the challenge, (ii) in room air inside the chamber before the exposure, (iii) at 12 ppm (44 or 56 mg/m3), and (iv) at 48 ppm (at 180 or 228 mg/m3).Results For both substances the TE groups showed a slight increase (deterioration) in the simple reaction-time task during chemical exposure, but not in the complex reaction-time task or in the digit symbol test of the Wechsler Adult Intelligence Scale. Contrary to reference subjects, the TE subjects did not show any improvement or learning effect in the digit symbol test over the chamber phases. n-Butyl acetate tended to affect cognitive functioning more obviously than toluene did. Suggestion or expectancy effects were not observed in any group in the clean-air base-line conditions.Conclusion The results do not support the notion that men with subjective hypersensitivity to chemicals would be more affected than healthy men regarding cognitive functioning during annoying solvent exposure below thresholds for acute neurotoxic effects."

"Objectives This study explored the effects of occupational exposure to solvents and noise on the hearing of rotogravure printing workers from São Paulo, Brazil.
Methods The study group comprised 124 workers exposed to various levels of noise and an organic solvent mixture of toluene, ethyl acetate, and ethanol. Data on work history, psychosocial aspects of the job, medical history, present health, stress, occupational and nonoccupational exposures to noise or chemicals, and life-style factors were collected through an interview. The participants underwent pure-tone audiometry and immittance audiometry testing. Their exposures to noise and solvents were assessed.
Results Forty-nine percent of the workers had hearing loss. From the numerous variables that were analyzed for their contribution to the development of hearing loss (age, tenure, noise dose, solvent concentrations in air, biological marker for toluene, job category, work and medical history items, smoking, alcohol consumption, work perception scores, nonoccupational exposures), age and hippuric acid (the biologic marker for toluene in urine) were the only variables that met the significance level criterion in the final multiple logistic regression model. The odds ratio estimates for hearing loss were 1.07 times greater for each increment of 1 year of age [95% confidence interval (95% CI) 1.03--1.11] and 1.76 times greater for each gram of hippuric acid per gram of creatinine (95% CI 1.00--2.98).
Conclusion The findings suggest that exposure to toluene has a toxic effect on the auditory system. Further research is needed on the mechanisms underlying the effects of toluene and on the adequacy of current recommended exposure limits."

Toluene is the common name for methylbenzene, a commercially important intermediate chemical produced throughout the world in enormous quantities. The general population is exposed to toluene mainly through inhalation of vapour in ambient air or from cigarette smoke. Apart from risks associated with occupational exposure, toluene poses special hazards to "glue-sniffers", who intentionally abuse solvent mixtures containing this chemical.
This report assesses close to 500 animal and human studies concerned with the effects of short- and long-term exposure to toluene, including its abuse. Environmental effects are also considered. While concluding that exposure of the general population and environment does not presently constitute a significant hazard, the report notes that solvent abuse may be associated with permanent pathological changes.

"Neurodevelopmental disabilities, including autism, attention-deficit hyperactivity disorder, dyslexia, and other cognitive impairments, affect millions of children worldwide, and some diagnoses seem to be increasing in frequency. Industrial chemicals that injure the developing brain are among the known causes for this rise in prevalence. In 2006, we did a systematic review and identified five industrial chemicals as developmental neurotoxicants: lead, methylmercury, polychlorinated biphenyls, arsenic, and toluene. Since 2006, epidemiological studies have documented six additional developmental neurotoxicants—manganese, fluoride, chlorpyrifos, dichlorodiphenyltrichloroethane, tetrachloroethylene, and the polybrominated diphenyl ethers. We postulate that even more neurotoxicants remain undiscovered. To control the pandemic of developmental neurotoxicity, we propose a global prevention strategy. Untested chemicals should not be presumed to be safe to brain development, and chemicals in existing use and all new chemicals must therefore be tested for developmental neurotoxicity. To coordinate these efforts and to accelerate translation of science into prevention, we propose the urgent formation of a new international clearinghouse."

"The study involved a group of 42 printing plant workers and a control group of 45 blood donors. At the working places, the ambient air-toluene concentration amounted from 141 to 328 mg/m(3). Sister chromatid exchanges (SCEs) were significantly elevated by three units in the exposed group. In this group, the concentration of urinary toluene metabolites was also considerably increased-hippuric acid was four times higher and the o-cresol and p-cresol fractions were twice as high. Results of toluene monitoring of ambient air- or blood-toluene concentrations did not show any relationships with individual SCE. While these SCE values revealed only a weak relationship with the corresponding hippuric acid data, a significant correlation with the cresols, which are known to be more genotoxic than hippuric acid, appeared in highly exposed workers. An attempt was made to consider the individual metabolic balance of toluene excretion products. For that reason individual cresol to hippuric acid ratios were calculated and related to corresponding SCE values. In all investigated subpopulations of the exposed group, this ratio correlated with SCE at a level of high significance. This strong interrelationship is a powerful argument for the genotoxic behavior of toluene. Furthermore, the individual metabolic balance, as a consequence of genetic polymorphism, should be considered in the discussion about genetic risk of toluene."