International Dioxin DevelopmentsJune 30, 2015
IARC Classifies 2,4-D in “Group 2B”
The International Agency for Research on Cancer (“IARC”), the specialized cancer agency of the World Health Organization, has evaluated the alleged carcinogenicity of the herbicide 2,4-dichlorophenoxyacetic acid (“2,4-D”) as well as insecticides gamma-hexachlorocyclohexane (“lindane”) and dichlorodiphenyltrichloroethane (“DDT”).
A 26-member working group from 13 countries convened by the IARC Monographs Programme classified the insecticide lindane as carcinogenic to humans (Group 1), finding “sufficient evidence” in humans for the carcinogenicity of lindane for non-Hodgkin lymphoma (“NHL”).
The IARC classified the insecticide DDT as probablycarcinogenic to humans (Group 2A), based on “sufficient evidence” that DDT causes cancer in experimental animals and “limited evidence” of its carcinogenicity in humans. The IARC said that epidemiological studies found “positive associations between exposure to DDT and NHL, testicular cancer, and liver cancer” and “strong experimental evidence that DDT can suppress the immune system and disrupt sex hormones.”
By contrast, the IARC classified the herbicide 2,4-D as only possibly carcinogenic to humans (Group 2B), based on “inadequate evidence” in humans and “limited evidence” in experimental animals. According to the IARC:
[E]pidemiological studies did not find strong or consistent increases in risk of NHL or other cancers in relation to 2,4-D exposure.
The Group 2B classification keeps 2,4-D in the same group as aloe vera, coffee, and pickled vegetables.
In a statement, one of the world’s leading crop protection and specialist seeds companies observed that 2,4-D “is the most researched crop protection molecule in the world, with more than 70 years continuous research that has kept pace with increasingly stringent regulatory requirements and technical advancements.” It noted that the “world’s leading regulatory agencies have not classified 2,4-D as carcinogenic and continue to assess it as being safe to use when done so according to label directions.”
Since its introduction in 1945, 2,4-D has been widely used to control weeds in agriculture, forestry, and urban and residential settings.
Vietnam Reportedly Examining Whether Tea Exported to Taiwan Contained Dioxin
Vietnam’s minister of agriculture reportedly has asked for an investigation to determine whether some black tea exported to Taiwan contained traces of dioxin.
Responding to concerns from Taiwan that certain shipments of black tea from Vietnam might contain dioxin, Vietnam’s minister of agriculture, Cao Duc Phat, called for the investigation, according to news reports.
The vast majority of tea imported into Taiwan is from Vietnam. The Vietnam minister of agriculture has asked local officials to determine if tea did contain traces of dioxin and, if so, to also determine the production point at which dioxin was introduced into the tea.
Late last year, around 200 tons of tea from Lam Dong, Vietnam, a province in the country’s Central Highlands region, that had been held at customs over dioxin rumors was permitted to enter Taiwan.
Vietnam Study Finds Dioxin Emissions from Incinerators
Incinerators in Vietnam that burn industrial and medical waste are discharging dioxin, according to a new study by Vietnam’s Steering Committee 33 and Vietnam’s Ministry of Natural Resources and Environment.
According to news reports, the study found that incinerators caused most of the dioxin discharged in the country.
The lead researcher, Le Ke Son, was quoted in a news report as saying that this was the first time that “Vietnam admits that there’s dioxin discharged from industrial activities besides from dioxin left from the war.”