The New Straits Times, June 14, 1999
Q: GIVEN the current dioxin scare in the food chain, can you please highlight the effects of dioxin on human health?
A: DIOXIN is a well known cancer-causing toxic chemical. It has received little attention despite being one of the most toxic unwanted byproduct ever to be studied to date. The sources of dioxin are entirely man-made since it is rarely, if ever, found in nature. It was introduced by man at the beginning of this century through the chemical manipulation of common table salt (sodium chloride), and for the first time making available free chlorine, and eventually a vast array of "chlorinated hydrocarbons".
It has been well documented that dioxin is released when a group of "chlorinated hydrocarbons" are used and processed in factories, ranging from those dealing with chemicals, pesticides, metal as well as paper, or otherwise as the result of burning in incinerators. According to Greenpeace, the biggest source of dioxin discharges comes from manufacturers on popular plastic, polyvinyl chloride (PVC).
In 1995, a US Environmental Protection Agency (EPA) study reviewed the health impact of dioxin, and mentioned numerous problems like: immune system toxicity, central nervous system toxicity, hormonal disruptions as well as a variety of cancers. Others reported the impact of dioxin on normal growth and the development of the young, including behavioural effects and learning disabilities. The basic message is that dioxin is very toxic and that the general public is not adequately protected from such effects.
Acute early symptoms to dioxin exposure include chemical burns of the skin, mucus membranes and eyes, nausea and vomiting as well as severe muscle pains. After a latency of several weeks, various skin manifestations like cloracne and hyperpigmentation may occur. Damage on the liver and nervous system (polyneurophathies) is frequently noted. Elevated blood lipids are common and may persist.
In cases where the situation remains unchecked, all these combined sources of dioxins can have a grave impact on the environment and consequently on our health, especially of our children. This unfortunately is not all. Dioxin, like so many pollutants, can also contaminate water sources as shown by a study on the Great Lakes in the US. The sources of dioxins are said to originate from hospital waste incinerators as well as commercial medical waste incinerators. Eventually it will creep into the human food chains and become part of our diet.
According to the US EPA, a routine dietary exposure through mainly red meat, fish and dairy products has produced an average body burden estimated to be 13 manograms of dioxin per kilogramme of body weight (ng/kg).
Likewise, a report submitted to the UK Department of Health recently showed that breast-fed infants are receiving up to 17 times the tolerable amounts of dioxin and polychlorinated biphenyls (PCBs).
The report, carried out as part of a wider World Health Organisation survey, found that the daily estimated dietary intakes of dioxins and PCBs by breast-fed infants in 1993 and 1994 were 170 picograms per kilogramme body weight at two months and 39 picograms per kilogramme body weight at 10 months.
Both figures are higher than the tolerable daily intake recommended by the WHO, that is 10 picograms per kilogramme body weight a day. Similarly the UK Committee in Toxicity of Chemicals in Food, Consumer Products and the Environment also found that infant and young children who take certain bottled fish liver oils may have exceeded the tolerable amounts of dioxins and PCBs.
In short, what is being experienced in Europe and the rest of the world today is not new. Indeed the threat of dioxins to public health has been overlooked in many countries. For Malaysia, some of the above-mentioned sources are already present in the country, beginning with automobile emissions. Since dioxin is also being released as a byproduct in leaded petrol, its toxic effect will invariably be felt sooner or later.
It is only a matter of time that Malaysia too has its own share of industries, including the steel and cement production industries where dioxins too could be released as a byproduct into the environment as reported in many other countries. The use of leaded petrol too is known to emit nine times as much dioxin per gallon of fuel as compared to the unleaded ones.
As late as 1995, despite adherence to the legislated emissions levels stipulated, the US Environmental Protection Agency (EPA) is still discovering how damaging dioxin is to humans and the environment.
Dioxin is often one of the many components of gaseous emissions called "flue gas" which despite being "washed" through a cleaning process may still contain some residues.
The question that needs to be asked is whether Malaysians are prepared to face the impending dangers of dioxins. More importantly, are we taking any concerted effort to prevent such pollutants from playing havoc with our environment?
