Sunday, April 24, 2005

Color vision and solvents

This report is one of several looking for neurobehavioral effects of organic vapor exposures at levels below recommended exposure limits. Early on, occupational health investigations attempted to cobble together various computer based variants of psychological tests as measures of impacts. The paper and pencil versions were likely validated in some way, at least large numbers of people took them. Computer based versions were less widely used. A long review would be needed to compare solvent effect levels with alcohol, psychoactive medication, sleep deprivation and other modifiers. BrooklynDodger opines that these test batteries are insensitive to substantial effects, and would have little impact on allowable exposure to solvents.

The report below goes another way: instead of examining variation in complex cognitive functions, why not look at very precise effects on the sensory apparatus.

Effects of styrene on color vision have been published before.

In paraphrase of abstract, styrene exposure and color vision was studied at Swedish reinforced plastic plants. Current exposure varied between 0.3 and 96 mg/m3. Cumulative past exposures varied from 18 to 4455 mg years/m3, and an index of lifetime weighted average exposure varied from 5 to 129 mg/m3. ... Analyses of variance revealed effects color vision. This study thus indicates that styrene exposure even at levels below the current Swedish OEL of 20 mg/m3 may affect color vision negatively.

The OSHA PEL for styrene is 100 ppm or 420 mg/M3. The ACGIH TLV is 50 ppm or 210 mg/M3. For risk assessment purposes, a decision whether hurting color vision is a central nervous system effect on higher and more conferning nervous system function.


Environmental Toxicology and Pharmacology Volume 19, Issue 3 , May 2005, Pages 511-516

Low-level styrene exposure and color vision in Swedish styrene workers

Anders Iregrena, , , Ann-Christin Johnsonb, c and Per Nylénd a

National Institute for Working Life, Risk Assessment Group, Box 210, SE-171 77 Stockholm, SwedenbKarolinska Institute, Unit of Audiology, Department of Clinical Science, Stockholm, SwedencNational Institute for Working Life, Work and the Physical Environment, Umeå, SwedendNational Institute for Working Life, Department of Ergonomics, Stockholm, Sweden Available online 3 February 2005.

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