The area of Taiwan is about 36,000 km², approximately one ninth the size of Malaysia, however, Taiwan has a larger population size (over 23 million) than Malaysia. Being one of the most densely populated area on Earth plus decades of emphasis on economic development, human activities has generated tremendous environmental burden on this small island-state and the sea around it.

In the early 1960s, the newspaper began reporting about introducing Japanese technology of making refined rice bran oil. It was not until 1975 that the rice bran oil was promoted by the governmental agency (Food Industry Research and Development Institute) as the new healthy cooking oil. In October of 1979 , a mysterious disease that spread around Taichung and Changhua area was finally confirmed to be linked to PCBs-contaminated rice bran oil. According to official statistics, 2,061 people in central Taiwan were affected by this massive poisoning incident.

Hui-Ming School and Home for the Blind Children was the first institution to report the mysterious disease (chloracne) that infested 167 blind children, teachers and staff.
The same type of oil processing machine has been identified as the culprit for both the Yusho(Japan, 1968 ) and Yucheng episodes as well. No compensations were paid to the victims, the oil making and retailing companies had transferred their properties before the court made its final verdict. Decades of follow-up studies have cited the adverse health effects of the victims and children born from the victims. The government had promised the full medical care for the victims. Through these years, the Yucheng victims found themselves stigmatized and neglected by the health care institutions when they seek frequent medical care because of their impaired immune and endocrine functions.

Some victims of Yusho in Kyushu areas had visited the Yucheng victims more than once in the 1980s. Civil movements and journalism were spurred by the Yucheng incident and inspired the founding of the first consumers' protection NGO in Taiwan, the Consumers' Foundation in 1980.

Of the 39 fetuses in utero during the active exposure, 9 died at or around birth.
Children born to mothers exposed to PCBs became a cohort group for the study of the PCBs tetratogenic effects. These children, so called "Cola-babies" because of their dark pigmented skin, were born with delayed development, scoring low in IQ test, pigmentation of head, face and genitals, shorter penis [1].
Children born up to 6 years after their mothers' exposure were as affected as children born within a year or two when examined at 6 and 7 years of age. CThe effect persisted in the children up to the age of 7 years, and children born long after the exposure were still affected. Other scientists argued that the extreme toxic/ tetratogenic effects should be attributed largely to the heat-degradation products of PCBs, namely dibenzofurans and quaterphenyl [2].

Black color of nose (PCB poisoning)

Acbeform eruptions (PCB poisoning)

The government has subsequently taken critical steps in setting regulations to curb the problem. All PCBs use has been exclusively imported. PCBs are listed as controlled chemicals for import by the Bureau of Industrial Development since 1972. The import of PCBs was halted in 1980 due to the Yucheng incident, and its application in food processing was prohibited as well.

In 1980, the import of PCBs was halted, and its use in food production was prohibited. The Environmental Protection Administration of Taiwan (Taiwan EPA) was officially established in 1987. The Toxic Chemical Substances Control Act was announced and went into effect in 1986. On June 22, 1988 the Taiwan EPA listed PCBs as controlled substance under the Toxic Chemical Substances Control Act. PCBs were listed as Class I and II controlled toxic chemical substance, where PCBs comes first in the list. Production, import, retail and use were prohibited accordingly.

PCBs are found mostly in capacitors and transformers produced before May of 1980. Because such products have been in use for over twenty years they present a constant threat of leaks and environmental contamination. To improve control of PCBs, on May 26, 1995, the EPA decreed that with the exception of experiments, research and education, all use of PCBs would be banned as of December 31, 2000. The EPA further stipulated that all PCB containing capacitors and transformers not in use should be immediately removed, reported as a hazardous waste, and properly disposed of according to the Waste Disposal Act. However, the EPA emphasized that capacitors produced from June 1980 to December 1982 cannot be tested because they are in use may be used until the end of their life expectancy.

Toxic Chemcial Substance management in Taiwan began with the promulgation of the Toxic Chemical Substances Control Act. Taiwan EPA has already listed 252 types of toxic chemicals to guard against the dangers posed by these substances.

According to the estimation of the Taiwan EPA, Taiwan produced 1.93 million tons of hazardous waste in 2000, and the treatment capacity is about 0.93 million tons annually, those disappeared wastes end up illegally dumped around the island. EPA's statistics shows at least 175 illegal dumpsing sites of industrial waste have been identified [3].

Some of the PCB-related hazardous waste sites in Taiwan have been identified and remediation plans have been undergoing in areas such as Erhjen River and Ta Fa Industrial Park. The Erhjen River is located in the southwest of Taiwan. High levels of PCBs, PCDD and furans have been found in the sediments and fish sample since early 1980s. At the hay day of the open-air cable burning, the Wanli area by the Erhjen river, the abortion, stillbirth and birth abnormality rate was very high, especially the anencephaly (baby born without brain). When fish samples were tested with high levels of furans and dioxins, the government banned the import of scrap metals and subsquently relocated the metal smelting industries to Ta Fa Industrial Park in the nearby Kaohsiung city. This river is considered one of the most polluted river in Taiwan due to its vicinity had been the ground for scrap metal processing, open-air cable burning between the 70s-90s [4]. Most of the ship dismantling and scrap metal processing industry has been moved to China and other Asian countries.

The Erhjen River has long been polluted by scrap metal smelters, and that most smelters currently use illegal equipment or operate in unlicensed buildings. The pollution from these operations has spread to Kaohsiung County, Tainan City and Tainan County. Over the past 20 years governments from the three have often organized joint inspection teams, but have consistently failed as smelters went from open air to underground operations.

In 2000, Taiwan EPA decided that cleanup of the Kaoping, Erhjen and Chiangchun rivers would be given top priory, and set aside NT$230 million in the 2001 budget for this work. On September 2001, the EPA announced formation of the a taskforce charged with cleaning up pollution from illegal smelting operations in the Erhjen River, putting cleanup of the Erhjen among the most pressing of the EPA's current jobs. There are about 60 smelting operations, most of them illegally operated should be removed from the banks of the river.

Erhjen river

Wanli

Smelters Around the Erhjen River

Studies on the bioaccumulation of PCBs in river fish revealed that southern Taiwan is more polluted than the north, which is correlated with the industrial use mentioned, while the concentration of PCBs in fish has decreased [6] . Studies of PCBs and dioxins from human placenta and breast milk had been analyzed over the recent years. These studies are beginning steps for establishing background data of PCBs concentration in Taiwanese population [7]. As to the study of marine mammals, PCBs concentrations and TEQs in cetaceans from Taiwan coastal waters were similar to the results from Philippines, British Columbia and Florida coast [8].

In December 5, 2000, the findings of a TEPA study became the headline news that fish from three major rivers in southern Taiwan contained high concentration of PCBs. The public was advised not to consume the viscera of fish caught in Erhjen,
Tonkang and Kaoping Rivers. The result confirmed what environmental groups have long suspected, for numerous hog farms, industries and dumpsites for metal smelting plants had been discharging waste through pipelines into the river[6] .

Again in December 23, 2000, seafood unsafe for consumption became the headline news. Analysis of 30 species of sea fish purchased from markets in Hsinchu area revealed that 14 species were tested positive of organo-chloride pesticides long banned in Taiwan. Thirteen percent of the fish sample contained levels of chemical residues exceeding the safety threshold. Another water quality monitoring project showed that 45.8% of the rivers were tested positive for nonylphenols, and rivers in the northern Taiwan were the most polluted.

It took a massive poisoning episode to teach a nation about an awkward chemical named Polychlorinated Biphenyls. Evidence shows that banning the use of PCBs has gradually lowered the residual levels of PCBs in Taiwan, however, the public concerns for PCBs is regenerated for their endocrine disrupting effects. We now face tough choices on selecting every bite we take, especially fish and shellfish. We sincerely hope that the Yucheng episode or events like so will not take place in your countries. To prevent than to heal, it takes precautions on every side.

References:

1. Chen YC, Guo YL, Hsu CC, Rogan WJ. (1992) Cognitive development of Yucheng ("oil disease") children prenatally exposed to heat-degraded PCBs.
   JAMA. 268(22):3213-8.
   
2. Guo YL (2000) Health effects associated with perinatal exposure to environmental hormones:the polyhalogenated aromatic hydrocarbons. In the First Environmental Hormones Conference, Taipei, Taiwan.
   
3. Hsing HJ, Wang FK, Chang CD. Hazardous waste importation, exportation, and control strategies of Taiwan. China Technical Consultant Inc.
   
4. Ling YC, Soong DK, Lee MK. (1995) PCDD/DFS and coplanar PCBs in the sediments and fish samples from the Erhjen river in Taiwan. Chemosphere 31: 2863-2872.
   
5. Huang JH. (1997) Industrial waste treatment in Taiwan. Industrial Development Bureau, Ministry of Economic Affairs, Taiwan.
   
6. 
   
7. Chao HR, Wang SL, Yu ST, Yu HY, Lin LY. (2002) 2,3,7,8-substitued PCDD/F levels and its related factors in Taiwanese primipara human milk. In The 2nd Environmental Hormones Conference (Taipai, Taiwan): 58-63.