November 20, 1995
Ciba Withdraws Isazofos After Two Deaths
Ciba-Geigy has temporarily withdrawn its insecticide Miral
500 CS (active ingredient isazofos) following three serious
poisoning incidents in Africa and Latin America linked to use
of the product. Miral is currently sold in 16 countries, with
sales between US$800,000 and $1.6 million per year. Ciba-
Geigy, the sole producer of isazofos, is still investigating
the cause of the incidents. According to a company
spokesperson, "We don't understand it. Our studies show that
it could not happen." Ciba reports that the product is a
capsule suspension formulation with lower dermal and oral
toxicity than earlier formulations. The World Health
Organization classifies isazofos class Ib, "highly
hazardous."
Two of the incidents resulted in deaths. In Colombia, a
coffee plantation worker died in June 1994 from lung edema
after becoming sick while using Miral. In July 1994, two
workers were hospitalized in the Dominican Republic after
showing symptoms of organophosphate poisoning; one of the
workers later died. At a banana plantation in Cote d'Ivoire,
four workers were hospitalized in May 1995, after heavy rains
disrupted crop spraying.
Ciba states that preliminary reports show that workers did
not follow instructions when using Miral. However, the
company also concedes that tropical conditions may be another
possible cause, since heat may have broken down capsules,
releasing the toxic ingredients. The company is currently
conducting studies on the stability of the capsules under
tropical conditions.
Commonly, pesticide risk assessments developed in Northern
countries are used to determine risk and set standards in the
South. This practice is problematic, however, because
standard risk assessments assume temperate climatic
conditions and assessments are derived from laboratory
experiments which do not take into account field conditions,
synergistic effects or the hazards of non-active ingredients.
In tropical climates, higher temperatures and humidity can
increase chemical toxicity and cause a range of physiological
responses exacerbating pesticide hazards for people. For
example, heat may cause water loss, basal metabolism changes
and circulatory disturbances which may increase pesticide
toxicity, and humidity causes swelling of the surface layer
of the skin, enhancing chemical uptake. Moreover, protective
equipment is often not available in developing countries, and
it is essentially impossible to wear impermeable protective
gear in tropical conditions.
Ciba claims there have been no Miral problems other than the
three poisoning incidents; however, the recall has been
extended to use on all crops in addition to bananas and
coffee. Approximately 80% of Miral's use is to control
insects and nematodes on potatoes and soybeans. Once studies
are completed, Ciba plans to relaunch the product and has
stated that they will work in close collaboration with
registration authorities.
Ciba-Geigy remains one of the leading agrochemical producers
worldwide, reporting "better than expected" sales of US$2.8
billion for the first three quarters of 1995. In 1994 Ciba
led the agrochemical industry with sales of US$2.8 billion.
Source: Agrow, October 6, 1995.
Contact: Pesticide Action Network North America (see below for contact
information)
===========================================================
| Pesticide Action Network North America (PANNA) |
| |
| Phone:(415) 541-9140 Fax:(415) 541-9253 |
| Email: panna@panna.org http://www.panna.org/panna/|
| PANNA, 116 New Montgomery, #810, San Francisco, CA 94105 |
| |
|*To subscribe to PANUPS send email to MAJORDOMO@igc.apc.org|
| with the following text on one line: subscribe panups |
| To unsubscribe send the following: unsubscribe panups |
| |
|*For basic information about PANNA, send an email message |
| to panna-info@igc.apc.org |
===========================================================