Styrene exposure

Results of studies on animals have indicated that styrene treatment (0.5 g per kg body weight) alters dopaminergic function in some brain regions that are important in the initiation and control of movement. However, the deficits in motor function resulting from styrene exposure were not permanent and the functions returned to control levels after cessation of such treatment (Chakrabarti, 2000). 

Description of the Model. The Corley chloroform PBPK model was based on an earlier PBPK model developed by Ramsey and Andersen (1984) to describe the disposition of styrene exposure in rats, mice, and humans. A schematic representation of the Corley model (taken from Corley et al. 1990) is shown in Figure 2-5 with oral, inhalation, and intraperitoneal routes represented. The dermal route of exposure is not represented in this model however, others have modified the Corley model to include this route of exposure (see below). Liver and kidney are represented as separate compartments since both are target organs for chloroform. 

An increased incidence of chromosome aberrations and micronuclei in peripheral lymphocytes have been reported in occupationally exposed workers. Additional studies have found a slight increase in the incidence of sister chromatid exchanges, whereas no increase has been found in several other studies. Sister chromatid exchange and chromosomal aberrations were induced in vivo in rodents and in vitro in human lymphocytes. Both DNA and protein adducts are formed in humans after styrene exposure. 

Harkonen H, Lehtniewi A, Aitio A Styrene exposure and the liver. Scand J Work Environ Health 10 59-61,1984... 

Using data collected in the population-based case-control study of cancer among male residents of Montreal, Canada, described in the monograph on dichloromethane (see this volume), Gerin et al. (1998) carried out an analysis focusing on cancer risks in relation to benzene, toluene, xylene (see this volume) and styrene exposure. For these analyses, the control group for each case series consisted of a combination of the 533 population controls with 533 cancer controls selected at random from the pool of eligible cancer controls. Fifteen per cent of the entire study population had been exposed to toluene at... 

The issues of styrene exposure to the human have been reviewed (37). Styrene has been found to be metabolized to styrene-7,8-oxide by cytochrome P450-IIE1 (38). 

Droz, P.O., and M.P. Guillemin. 1983. Human styrene exposure. V. Development of a model for biological modeling. Int. Arch. Occup. Environ. Health 53(l) 19-36. 

Harkonen, H. 1977. Relationship of symptoms to occupational styrene exposure and to the findings of electroencephalographic and psychological examinations. Int. Arch. Occup. Environ. Health 40(4) 231-239. 

Styrene exposures between 50 and 100 ppm have been associated with neurological effects including decrements in color discrimination, nerve conduction, and neurobehavioral performance. These changes appear to be transient, with improvement... 

Bergamaschi E, Smargiassi A, Mutti A, et al Peripheral markers of catecholaminergic dysfunction and symptoms of neurotoxicity among styrene-exposed workers. Int Arch Occup Environ Health 69 209-214,1997 Challenor J, Wright D Aggression in boat builders a search for altered mood states in boat builders exposed to styrene. Occup Med (Lond) 50 185-192, 2000 Cherry N, Rodgers B, Venables H, et al Acute behavioural effects of styrene exposure a further analysis. British Journal of Industrial Medicine 38 346-350, 1981 Cherry N, Hutchins H, Pace T, et al Neurohehavioural effects of repeated occupational exposure to toluene and paint solvents. British Journal of Industrial Medicine 42 291-300, 1985... 

Harkonen H, Lindstrom K, Seppalainen AM, et al Exposure-response relationship between styrene exposure and central nervous functions. Scand J Work Environ Health 4 53-59, 1978... 

Viaene MK, Pauwels W, Veulemans H, et al Neurobehavioural changes and persistence of complaints in workers exposed to styrene in a polyester boat building plant influence of exposure characteristics and microsomal epoxide hydrolase phenotype. Occup Environ Med 58 103-112, 2001 Welp E, Kogevinas M, Andersen A, et al Exposure to styrene and mortality from nervous system diseases and mental disorders. Am J Epidemiol 144 623-633,1996 White DM, Daniell WE, Maxwell JK, et al Psychosis following styrene exposure a case report of neuropsychological sequelae. J Clin Exp Neuropsychol 12 798-806, 1990... 

Yokoyama K, Araki S, Murata K Effects of low level styrene exposure on psychological performance in FRP boat laminating workers. Neurotoxicology 13 551-556, 1992... 

Measurements of styrene in venous blood at the end of the workshift and/or prior to the next shift have been recommended by the ACGIH. Monitoring of urinary metabolites of st5Tene has also been recommended by the ACGltf at the end of the week, even though they are not specific to styrene exposure. Styrene in exhaled air after the end of exposure was not recommended as a BEl because the levels would be too low to detect, leading to uncertainties. 

A. Saamanen, Methods to Control Styrene Exposure in the Reinforced Plastics Industry, Publications of the Technical Research Centre in Finland No. 354, Espoo, 1998. 

Huff J, Infante PR Styrene exposure and risk of cancer. Mutagenesis 2011 26 (5) 583-584. 

Kolstad HA, Ebbehpj N, Bonde JP, Lynge E, Albin M. Health effects following occupational styrene exposure in the reinforced plastics industry. Ugeskr Laeger 2012 174 (5) 267-270. 

Gotell P, Axelson O, Lindelof B (1972) Field studies on human styrene exposure. Work Environ Health 9 76-83 Haddad FS, Cobb AG, Bentley G, Levell NJ, Dowd PM (1996) Hypersensitivity in aseptic loosening of total hip replacements. The role of constituents of bone cement. J Bone Joint Surg Br 78 546-549... 

A significant increase in 8-hydroxy-2 -deoxyguano-sine in the blood of 17 workers exposed to styrene compared to 67 non-exposed healthy volunteers provided a good indication that styrene exposure can result in generation of hydroxyl radicals and oxidative DNA damage (Marczynski et al. 1997). 

Reduction of current 100-ppm styrene exposure limit to 50-ppm by the Occupational Safety Health Administration... 

Once the research team had observed and pinpointed the behaviors and conditions that resulted in the most styrene exposure, the important task was to identify those that could reduce the exposure. The team consulted the workers who handled styrene during the manufacturing processes for suggestions about how to restructure their work to reduce their exposure to the chemical. The researchers also reviewed more than 250 professional publications for recommendations. 

The researchers accomplished their goal of changing workers behavior, but they were not satisfied with only this. They also wanted to make sure the changes lasted. About two years after the program had ended in all three plants, the researchers were able to check back with one of the plants to see if the safety practices had maintained. They found that several of the safety practices as well as the reduction in styrene exposure had lasted for the two years. Next, the team reimplemented the feedback and safety awards initially used and found the workers responded... 

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