84 Agricultural Harm to the Environment
and over 200 per cent increase in agricultural labour and input costs over three years
(World Development Index, 2003). Meanwhile, open trade with neighbouring
Colombia and Peru has permitted the import of cheaper commodities. As a result of
a trend towards increased input costs and lower potato prices, in 2003 Carchense
farmers responded by decreasing the area planted in potato from about 15,000ha in
previous years to less than 7000ha. It remains to be seen how farmers ultimately will
compensate for the loss of competitiveness brought about by dollarization.
Carchi farmers of today rely on insecticides to control the tuber-boring larva
of the Andean weevil (Premnotrypes vorax) and a variety of foliage damaging insects.
They also rely on fungicides to control late blight (Phytophtera infestans). One
economic study of pesticides in potato production in Carchi confirmed that farm-
ers used the products efficiently (Crissman et al, 1994), and later attempts during
the 1990s by an environmental non-governmental organization (NGO) to pro-
duce pesticide-free potatoes in Carchi failed (Frolich et al, 2000). After 40 years
inorganic fertilizers and pesticides appear to have become an essential part of the
social and environmental fabric of the region (Paredes, 2001).
Pesticide Use and Returns
Our 1990s study of pesticide use found that farmers applied 38 different commer-
cial fungicide formulations (Crissman et al, 1998a). Among the fungicides used,
there were 24 active ingredients. The class of dithiocarbamate contact-type fungi-
cides were the most popular among Carchi farmers, with mancozeb contributing
more than 80 per cent by weight of all fungicide active ingredients used. The
dithiocarbamate family of fungicides has recently been under scrutiny in the
Northern Andes due to suspected reproductive (Restrepo et al, 1990b) and muta-
genic effects in human cells (Paz-y-Mino et al, 2002). Similar concerns have been
raised in Europe and the US (USEPA, 1992; Lander et al, 2000).
Farmers use three of the four main groups of insecticides in 28 different com-
mercial products. Although organochlorine insecticides can be found in Ecuador,
farmers in Carchi did not use them. The carbamate group was represented only by
carbofuran, but this was the single most heavily used insecticide – exclusively for
control of the Andean weevil. Carbofuran was used in its liquid formulation, even
though it is restricted in North America and Europe due to the ease of absorption of
the liquid and the high acute toxicity of its active ingredient. Another 18 different
active ingredients from the organophosphate and pyrethroid groups were employed
to control foliage pests, though only four were used on more than 10 per cent of
plots. Here the OP methamidophos, also restricted in North America due to its high
acute toxicity, was the clear favourite. Carbofuran and methamidophos, both classi-
fied as highly toxic (1b) insecticides by the WHO, respectively made up 47 per cent
and 43 per cent of all insecticides used (by weight of active ingredient applied). In
sum, 90 per cent of the insecticides applied in Carchi were highly toxic. A later survey
by Barrera et al (1998) found no significant shifts in the products used by farmers.