Benzene normally found in atmosphere
Despite the high levels of benzene recorded in the first sample analysis report of the air quality tests done two days after fire broke out at the Riverton City disposal site in St Andrew, subsequent reports are expected to show the levels reduced to normal.
Air quality measurements were done at three separate locations for the period March 13-14, two days after a considerable portion of the dump was reportedly set on fire by arsonists, causing heavy clouds of smoke to affect at least four parishes for two weeks and send some 842 persons to health centres.
According to that first report, in the Half-Way Tree area, the measurements were 7.87 micrograms per cubic meter, while the measurements from the other two locations along Spanish Town Road, closer to the dump, were 84.2 and 83.0 micrograms per cubic meter.
Of the 46 substances recorded in the sample analysis report, benzene recorded the highest micrograms per cubic meter.
Minimum detection levels for benzene in the atmosphere is 0.2 micrograms per cubic meter, noted Dr Kevin Harvey, permanent secretary in the Ministry of Health, while speaking Tuesday with The Gleaner/Power 106 newsroom. He added that this was just a one-off report.
Benzene, an organic chemical compound that contains carcinogenic properties, is normally found in the atmosphere. It is emitted from several sources, including motor vehicles, cigarettes, tobacco, paints, solvents, burning charcoal, forest fires, just to name a few. Several manufacturers use benzene in plastics, glues, rubbers, lubricants, detergents, dyes, drugs and pesticides, among other things.
One of the most manufactured chemicals in the United States, over the years, its use has been reduced because of its cancer-causing properties.
Symptoms such as drowsiness, dizziness, rapid or irregular heartbeat, headache, tremors and confusion can occur immediately after exposure to high levels of benzene.
Acknowledging that there was no World Health Organization established standard on the acceptable amount of benzene in the atmosphere, Harvey said what was important is the level of exposure.
low-level exposure
"Benzene is part of the environment ... , however, the levels vary. So if you live in the country areas, for example, the hills of Mandeville or up in the Blue Mountains, you might have a very low level of benzene exposure, less than one microgram per cubic meter. But in industrial cities like Kingston, where you have high numbers of factories and motor vehicles, the exposure is usually very high, where it could get up to 300," stated Harvey.
"However, the exposure to high levels would have to be continuous for you to have long-term health effects."
He continued: "I want to say what the specific long-term effect is, because benzene affects you in two major ways. One, it can affect your nervous system and, in high concentration, it can cause severe poisoning, brain damage, epilepsy, and various other things in high concentration. And that would only happen to persons who work in a benzene factory, for example, and got direct exposure. You would have to have persistent, long-term exposure at these higher levels to have those effects. The second effect is what we would call a bone marrow suppression."
The health ministry had said the benzene levels in the report were at the highest level ever recorded by the ministry.
Harvey said other hazardous substances from the smoke would have irritated the respiratory system, causing various respiratory problems.