March 26, 1999
Tokorozawa produce not a health threat: ministries
The level of dioxin in produce grown in Tokorozawa, Saitama
Prefecture, is not substantially above the national average and
does not
pose any threat to human health, according to a set of emergency
government studies released Thursday.
The Environment Agency, Ministry of Agriculture,
Forestry and Fisheries and the Health and Welfare Ministry conducted
joint research
on dioxin concentrations in spinach and tea, as well as in the
air, water
and soil, in response to the panic stemming from a Feb. 1 TV Asahi
report alleging that agricultural products grown near Tokorozawa,
an area with a high number of waste incinerators.
According to the government results, the levels found
"will not impact the health of people." The three government
organs, as well as
Saitama Prefecture, officially declared later in the day that
Saitama
produced tea and spinach safe for consumption.
Researchers found that 10 bunches of spinach packed
for shipping
yielded dioxin concentrations of .0085 to .15 picograms per gram.
A picogram is a one-trillionth of a gram.
The results are almost identical to those in a 1997
nationwide
survey by the Health and Welfare Ministry, which found .025 to
.37
picograms.
According to the ministry, an average diet including
spinach
with levels found in and around Tokorozawa would result in consumption
of between 2.3 and 2.4 picograms of dioxin a day, less than the10
picogram limit set by the ministry.
However, the Health Ministry is currently working with the Environment Agency to review the standard and will likely lower the limit to between 1 and 4 picograms, similar to those adopted by the World Health Organization, later this year.
Surveys of tea, for which Tokorozawa is famous, found
an
average of .81 picograms per gram, much lower than the 3.8 picograms
per gram found in a study by the Tokyo-based Environmental Research
Institute that were reported by TV Asahi.
Tea leaves steeped for one minute in water heated
to 90
degrees produced no detectable dioxin. Tea leaves left for five
minutes in 100-degree water produced a dioxin concentration of
.002
picograms per liter.