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Methanol
Expected Concentrations:
Methanol is a solvent that is commonly used to dissolve pseudoephedrine or ephedrine from cold pills. The levels of methanol during this process have not been measured and reported in the literature at this time but they are expected to be relatively low unless heating is conducted to increase evaporation or unless the operation is conducted in an enclosed space such as a basement. Evaporation, especially in enclosed spaces is an extreme explosion hazard. The methanol is frequently obtained from automotive fuel additive (HEET) or it can be purchased from a number of commercial sources. Other solvents can also be used.Current standards for airborne methanol exposure are as follows:
OSHA PEL |
NIOSH REL |
ACGIH TLV |
NIOSH IDLH |
200 ppm |
200 ppm / ST = 250 ppm |
200 ppm / ST = 250 ppm |
6000 ppm |
General Health Effects:
Methanol is frequently ingested by accident but may also be inhaled. In either case, it is believed that methanol is metabolized in the body to formic acid and formaldehyde. These metabolites result in a severe acidosis and effect the optic nerve potentially resulting in blindness. Symptoms of toxicity consist of nausea, dizziness, vertigo, abdominal pain, shortness of breath and visual symptoms (blurred vision, double vision, etc.). In severe cases, blindness may occur. Some individuals may enter a coma and die. Individuals who survive the coma are frequently blind.
Health Risks to Children:
Children with exposures to methanol are likely to have similar symptoms as do adults. Children may be more susceptible to pulmonary damage due to a greater lung surface area per body weight and a more rapid breathing rate.
Fetal Health Effects:
In one instance, exposure to a mixture of methanol and other solvents was reported to be linked to central nervous system birth defects in the fetus although other similar reports have not been available. Pregnant animals exposed to high levels of methanol have been found to have increased fetal absorption and a number of structural birth defects.
References
Proctor, N.H. , Hughes, J.P. 1978. Chemical Hazards of the Workplace. J.B. Lippincott Co. Philadelphia, PA 533 pp.
Proctor, N.H. , Hughes, J.P. 1978. Chemical Hazards of the Workplace. J.B. Lippincott Co. Philadelphia, PA 533 pp.
Salocks, C. and Kaley, K.B. Technical Support Document: Toxicity Clandestine Labs: Methamphetamine. Vol 1. , Number 10. Methanol. Cal/EPA. Office of Environmental Health Hazard Assessment. Sacramento, CA . 2003. 10 pp.
Supporting Documents
Technical Support Document: Toxicology
Clandestine Drug Labs: Methanol
Office of Environmental Health Hazard Assessment
Chronic Toxicity : Methanol
Office of Environmental Health Hazard Assessment
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