Nhiều
loại dung môi được sử dụng phổ biến trong công nghiệp cao su như hydrocarbon no
hoặc thơm (benzene, toluene, …) để làm sạch bề mặt cao su, dụng cụ, thiết bị hoặc
chlorinated hydrocarbon có trong các loại keo dính chống cháy và các hóa chất
khác. Tác động của chúng đến sức khỏe của công nhân được trình bày cụ thể bên
dưới.
…
5.
Solvents
Solvents
are used extensively in the rubber industry during the manufacturing process to
prevent tackiness. Solvents are also used to degrease and clean workshops.
Users must recognise where particular solvents are likely to occur, namely:
that aliphatic hydrocarbons are used for the freshening of rubber surfaces;
aromatic hydrocarbons (like toluene and xylene) are likely to be found in
rubber solutions; carbon disulfide is used in the traditional cold cure
process; and, chlorinated hydrocarbons (like methylene chloride) are used in
the production of non-flammable adhesives (a.8, a.9).
5.1.
Health Effects
The
main effects of solvents are irritation to the skin, eyes and lungs, headache,
nausea, dizziness and light-headedness. Exposure can impair coordination making
workers prone to falling-type accidents. A person may lose concentration or
have a reduced reaction time thus affecting judgment of important or difficult
tasks. These effects will vary and can be exacerbated by drinking alcohol. Very
high exposure, especially where adhesives are used in unventilated, confined
spaces, may cause unconsciousness and even death. A person who has been exposed
to solvents and feels their health has been adversely affected should seek
medical advice. Other effects vary according to the solvent, several are
reviewed here.
…
5.1.2. Toluene: C6H5CH3
Toluene
or methylbenzene is a monomethyl derivative of benzene. Toluene is used to
indicate the swelling index of rubber. Acute exposure to concentrations >200
ppm may result in headache, dizziness, irritation of the eyes, nose and throat,
paresthesia, incoordination, confusion and narcosis. Chronic exposure may give
rise to muscle weakness, abdominal pain, impairment of gait/balance, ataxia,
peripheral neuropathy and altered mental state. Enlargement of the liver and
neurobehavioural effects have been documented. Effects on the blood system
similar to benzene have been attributed to benzene being present as a
contaminant in some commercial batches of toluene. The 2000 UK occupational
exposure limit for toluene was 50 ppm (8-hour TWA reference period) with a
short-term exposure limit of 150 ppm (a.10).
…
Trích
đăng từ sách Health and Safety in the Rubber
Industry, Naesinee Chaiear, Smithers
Rapra Press, 2001, trang 15 – 16
(vtp-vlab-caosuviet)
