State of Chlorine Containing Pesticides in Uruguay
by Mr. Mario Boroukhovitch
Uruguay's economy is based mainly
on livestock and agriculture, that represent today 10-12% of P.B.I.(Internal
Gross Product)(12) The animal production (cattle and sheep meat, milk,
pork, poultry) represent 60% of the P.B.I of this sector, and the other
40% correspond to agriculture production (rice, citrics, barley and
other cereals, etc): Agriculture and livestock product and agroindustrial
produce 37% of the full enter holding in the country for export concepts.
The agriculture and livestock production
is affected by the attack of different pest, which produce important
damage. With the proposal to diminish the incidence of this dangerous
organisms, has implemented different control measures, and chemical
control was one of the alternatives.
Like in most countries of similar
characteristics, since the apparition in the world market of the organic
synthetic pesticides, after the Word War II, Uruguay had used these
products. Between this pesticides were the organochlorates insecticides.
At the end of the forties, it was
used hexachlorociclohexane (commonly commercially named Gammexane) for
the control of the swarms of locust (American Schistocerca = Schistocerca
cancellata) and later the uses of other chlorate insecticides for control
of local locust named "tucuras" (Orthoptera, Acrididae).
The extensive use of chlorate pesticides
in the sixties was for the insect control, mainly lepidopterous worms
in cereal crops (wheat, barley, oats, corn, sorghum), oilcrops (flax,
sunflower), industrial crops (potatoes, sweetbeet), and for soil insects
and cutting ants control. Also part of the farmers used organochlorates
insecticides for control of pest in vegetable and fruit crops.
In the livestock area, it was used
some chlorate pesticides for ectoparasites control.
National Authorities perceiving
the risks that can produce the wide use of the organic synthetic pesticides
in the agriculture, could produce, intended to minimize their risk throughout
the technical advice to the farmers who used these pesticides. In 1958
a supervised control service was established, and the main goal was
to avoid unnecessary wide applications of this pesticides. For this
reasons the Campaigns of locust control were transformed to "Campaign
of the fight against caterpillar and others pest insects"
This Campaign had an Aerial Service
Department with area applicant aircraft that make aerial applications
only authorized by official entomologist and farmers technicians.
The main organochlorates insecticides
first used in this Campaigns were DDT and endrin in aerial sprays ,
but others products as toxaphene, toxaphene-DDT, dieldrin, telodrin.
By inspections solicited by the
farmers, the entomologists of the Livestock and Agriculture Ministry
(M.A.P.) Plant Protection Department especially assigned to the "Campaign
of the fight against caterpillar and others pest insects", determinated
in each situation the necessity or not for proper control measures.
For such aspect as vegetative phase of the crop, type and amount of
damage, density of the pests, development stade of the insect, distribution
in the crop, presence of natural enemies (parasites and predators) and
its incidence, and attacks places in the crop were evaluated.
Likewise, the technician determinated
if were necessary make local 0 total treatment in the crop, type of
pesticide to use, doses and total volume of spraying for ha, especially
in the aerial applications.
In this manner, it could diminish
the treatment at only 30% of the total area inspected (2), which is
showed in the table VI.
This activity of technical assistance
at Official level, made by the Plant Protection Department (further
on Plant Protection Direction) in the eighties was transformed in a
monitoring service in extensive crops, making advertences about the
appearance of insect pest. This information was noted by technicians
and farmers and used for make decisions for pest control. This monitoring
work was extended as advertences about appearance of fungal diseases
in winter cereals (rust, fusarium, septoria and other phytosanitary
In 1968, in account the knowledge
of the problems of bioaccumulation of chlorates pesticides in the lipids
of animals and the men, raise general preoccupation to protect the national
consumer, but at the same time make not affect the meat and derivades
exportations. The Uruguayan Government decree 367/68 empowered at the
Livestock and Agriculture Ministry to regulate, and in the necessary
cases ban the application and destination of the pesticides of use in
livestock and plant protection, when it consider dangerous to public
By Livestock and Agriculture Ministry
Resolution dated 6/6/968 was banned the use of chlorate insecticide
formulated with aldrin, dieldrin, endrin, chlordane, heptachlor, gamma
isomer of H.C.H., DDT and endosulfan, destined to the control of insect
pest in grassfield and implanted and/or artificial prairies. It was
excepted the use of chlorinated insecticide for ant control in focussed
All the registrants of this insecticides
must add in the labels the phrase "Its must not use in grasslands
implanted and/or artificial prairies".
Other problems that general concern,
no only of the plant protection view, but of the consume population,
because can repercute in the human and animal health, was the insect
control of stored grains.
In 1973 was created in the Plant
Protection Research Center and Direction, a Department of Stored Grain
that realized a survey of the problem and developed a Campaign to control
insects in stored grain, recommending cleaning in treatment of the storehouses
and storing locals and the use of the adequate protestant insecticides.
In this recommendation was eliminated chlorated insecticides for all
the treatment in structures, empty bags and vehicles, authorizing only
their use for seed treatment.
Parallel it was started a Program
of Grain management, avoiding quality and quantity losses, and diminish
presence of micotoxines, and make inadequated the life conditions to
It was stated in the different inspections,
that in the years that the climatic conditions owed to reduce the sowing
areas of cereals (wheat, oats, barley, etc) the stored seeds treated
with chlorates pesticides were mixed with cereal grain and destined
to human and animal consume.
View the difficulties in this moment
to make analytical determination of residues of pesticides in 1977 with
the promulgation of decree 149/977 dated, march 15, 1977 yet today in
force was included banning chlorate insecticides not only in grassland
and prairies, but also in grain treatment destined for human and or
animal consumption and/or industrialization.
After the Committee for the study
of biological residues in meat at National level carnation in 1979,
the analytical laboratory of the Veterinary Research Center Miguel C
Rubino, collaborating with agronomic area were analyzed different wheat
and rice grain samples extracted by technicians of Plant Protection
Similar activity was realized by
the Technological Laboratory of Uruguay (L.A.T.U). The results of this
analysis area showed in the tables VIII, IX, X and XI.
In the same period, and with the
creation of the Toxicological Information and Advice Center (C.I.A.T.)
of the Clinics Hospital (University of the Republic), for agronomist
and medical initiative was developed an agromedical team integrated
also with veterinarian and chemicals technicians. Working jointly one
of the task of this team was to evaluate to organochlorates pesticides
contamination in Uruguay to determine the chlorate level in the blood
of exposed and don’t exposed professional way population (5) The
conclusions confirm that exist certain grade of organochlorates residues
in the general population. (Table XIII)
The exposed population presented
higher levels that the no exposed one. Residues did not concord strictly
with the pesticides in use at that moment, but reflected a greater grade
of exposition, the logical consequence of years working with different
organochlorates (14) HCB levels, product used for seed treatment of
diseases in wheat and other cereals, may be owing a use deviation of
treated seed that were incorporated at human or animal consumption,
violating the legislation at that moment (14). In the dieldrin event,
the residue values can be explained more for domestic use or a deviation
of agriculture use to household.
It attracted the attention the appearance
of important residues of DDT, since Uruguay did not import this product
for agricultural use after 1977.
This activity was continued and
in 1982 the conclusion and result were founded in the paper Clinical
and analytical control to an organochlorates pesticides exposed population.
Of the results can be concluded
that organochlorates impregnation values descended in the lapse of three
years in people with initial high, medium and low values, and descend
at the mid founded for no exposed populations in many cases (See table
XVI). The presence of these organochlorine levels in blood showed an
impregnation without clinical or paraclinical repercussion in those
three years. The most used insecticides in those moment - endrin and
endosulfan - don't leave residues because they have a quickly metabolization.
It was detected metabolites of others
chlorates pesticides which were used in agriculture in these moment.
Also existed interest in research in motherly milk. In this area can
be mention the paper* Pesticides organochlorates residues in human milk*(7)
in 1985. In all the samples were founded BHC, beta HCH, DDT and their
metabolites (ppDDT y ppDDE) and dieldrin at different levels. They didn't
detect polychlorinated biphenyls (PBCs).
These results indicate that the
use deviation of many organochlorates of agricultural use to domestic
use, the food contamination, especially treated seeds that deviate at
human or animal consume and organochlorates domestic insecticides, are
the reasons for the detected contamination.
An other paper "organochlorates
pesticides residues in umbilical cord blood": Comparation with
maternal level"(14) was detected in the most of the samples of
blood mother HCB, beta HCH, dieldrin and DDT and its metabolites residues.
Legal Restrictions and Prohibitions
of Organochlorates from 1977 to Present
The Ministry of Agriculture and
Livestock based in the recommendations of the General Directions of
Agronomic and Veterinary Services for Legal Resolution date 1/12/977
banned hexachlorociclohexane importation, manufacture, formulation and
sale for agricultural and veterinary uses. This action was the consequence
of deviation use from agricultural to veterinary. It is excepted for
this banned lindane (99% gamma isomer of HCH).
By Legal Resolution of Plant Protection
Direction dated May 19, 1988 the registration and sale authorization
of endrin was revoked, for all agronomic use, except parakeet control
(Myiopsitta monachus, Aves Psittaciformes), only been sale with official
authorization from Plant Protection Direction and no less 20 liters
containers. In account to endrin high toxicity to man, animals and the
environment, and in view that existed other actives to substitute them,
was limited its use. The parakeet control consists in endrin introduction
in the next entry.
In March 29 of 1989,by Plant Protection
Direction Resolution all the organochlorates pesticides used in seed
treatment were revoked. This included benzene hexachlorate (HBC) used
many years ago for your fungicide action in seed treatment. The HCB
residues were detected in exposed and no exposed populations at organochlorates
pesticides, before mentioned.
For Plant Protection resolution
dated September 22 of 1989 was revoked the register and sale authorization
of chlorate insecticides, permitting its use only for cutting ant control
with an active concentration less than 2,5% p/p or p/v., colorless in
red and it has to be more than 1 liter o 1 kg.
In Uruguay the cutting ants on special
Acromirex and Atta are a very big problem for many crops because of
the serious damage on them.
Other similar study performed in
Rio de la Plata and programme of monitoring and control on Uruguay River
was published in 1992 by Chemical Engineer Juan Miguel Moyano Recine
in its paper "Pesticides residues in rivers and seas" (13)
and the results of organochlorates in Uruguay River showed in the table
Also is necessary to distract the
inform realized by consultants of the Programme of the Environmental
National Study in the orbit of Presidential of Republic, with the support
of BID and OEA*.
The agreement between Ministry of
Transport and Public Work and the University of the Republic, through
Hydrographic Direction and C.I.A.T. started pesticides residues studies
in the Basin of Santa Lucia River had the objective to obtain information
about pesticide use and management in the Basin. In 1989 an inquiry
was made of farmers and applicators. There are a paper about this, named
"Pesticides on environment Risk criterion"(9). The Rio Santa
Lucia Basin is one of the potable drinking water source to Montevideo
and Canelones population.
Elimination Problem with the Organochlorates
It doesn't exist a survey of finished
or used lot, we know puntal situations of lots of chlorated insecticides
stored in sure locals. The elimination solution was burned in special
incinerator ovens with temperatures over 1200 centigrade grades. In
first instance it was thought to use the incinerators of cement manufactures
that operate in Uruguay, but have big difficulties for elimination of
solid residues and don't overtake the temperature mentioned. and it
is necessary search alternatives others.
Discussion about the Problematic
of Chlorated Insecticides in Uruguay
As other countries in the world,
use of chlorated insecticides in Uruguay was ample, since their entry
in the market, at the end of the forties.
The diffusion of scientific evidence
that showed adverse effects of this chemicals to man, domestic animals
and environment, carry on the Uruguayan Government, at initiative of
Ministry of Livestock and Agriculture, by decree 367/968 to authorize
at those Ministry to regulate and to ban, when it is necessary, those
livestock and agriculture pesticides, when it consider threat for human
health. Based in this normative, was resolved use prohibition of chlorates
insecticides to control insect that attack grasslands, and implanted
or cultivated prairies. In account the high incidence of cut ants in
this pasture fields, is permitted localized nest control of these insects.
The regulatory action obliged to intensify the use of others actives,
organophosphorous and organocarbamates, but also the use of microbiological
insecticide Bacillus thuringiensis, registered in Uruguay at middle
sixties, but being more expensive that other insecticides.
The substitution of chlorates to
organophosphorous and carbamates insecticides provoked a higher costs
in control treatments, in some circumstances higher risk of intoxications
and the necessity of realize different experiments for control insects.
Nevertheless this actions started chlorinated substitution process in
others crops, and the news to the farmers of practicable alternative
By Plant Protection resolution dated
November 22 of 1989 it were clarify that the before revocation mentioned
excepted endrin and endosulfan.
Finally, by Ministry Resolution
date on September 23 of 1997, all chlorate pesticide register were revoked,
except endosulfan and dodecachlor This last product formulated like
0,45% granulate toxic bait.
Of this manner culminate a restriction
and prohibition proceeding of this COPs, restricting the revision of
dodecachloro. The reason for no prohibited dodecachlor is due that in
Uruguay the farmer have preference use for the granular toxic bait in
ant control in fruticulture, horticulture, floriculture and mainly forest
cultures. The others toxic granules registries haven't the same efficient
control, according the farmers opinion.
Imports Statistics of Organochlorates
Insecticides in Uruguay
In Uruguay, with exceptions, pesticides
for veterinary or agronomic use are not manufactured here. Most of the
products area already formulated auxiliary substances are imported for
a local formulation.
Each one of the imported shipment
that is imported, is analyzed by the laboratories of the General Direction
of Agronomic Service and if the analytical results are coincident with
the official registration is liberated by custom authorities. General
Direction of Agronomic Services has an actual statistical information
in this field since sixties( 1,3).
At this respect, except dodecachloro
and endosulfan, the last shipment of chlorates imported was aldrin,
power formulation 2,5%(830 kgs a.i.), in 1991.
Tables I, II, Ill, IV and V show
the importation evolution of organochlorates insecticides in different
periods, and the comparative volumes of the others insecticides groups.
Pesticides Intoxications Statistics
The Toxicological Information and
Advisory Center (C.I.A.T.) had elaborated annual reports that include
different types of intoxication statistics. In the paper "Chlorates
insecticides intoxication"(l0) we reproduce in the tables XIX and
XX the consult about chlorates, according of intoxication type, ingress
way and age, between December 1975 and October 1978.
The most chlorated intoxication
is by accidental ingestion in children of suicide intent. The labor
intoxication is few.
In the Environmental contamination
area, there are information about river contamination as is showed in
the papers "Presence of organochlorates pesticides in exterior
Rio de la Plata an Maritime Front (11), 1987. The result is showed in
the table XXI. All the amounts respect to aldrin, dieldrin and DDT exceed
established limit to aquatic life, but all the values are lower for
human health criterion.
The initiating campaign to control
insects that attack stored grain, in 1973, was the opportunity to rationally
the use of preservative and curative insecticides, eliminating chlorated
insecticides use as structural treatments and avoiding use deviation
to treat directly stored grains destined to human and animal consummation.
At this respect, in the opportunity
of study the regulations about registry, importation and sale authorization
of agriculture pesticides, incorporated the use prohibition of chlorated
to treat grain destined to human and animal consummation and for industrialization.
The obligation of colorant add to treatment seed formulation, limited
yet more deviation stored seeds at human or animal consumption. Subsequently,
the chlorated seed treatment ban, eliminate of fact the use deviation
of seed to consume.
After, the use restriction of chlorates
insecticides only for cutting ant control, is other stage of the restrictions
process of this products and the use of others actives, as phosphorous,
carbamates and pyretroids insecticides, with similar effectively, but
without the chlorates problems. This chlorate restriction imply that
maximum concentration must no high than 2,5%, only for ant control,
and must be identified the chlorate formulation with adding colorants
for easy identification in the situation of deviation of use.
The use restriction of endrin, only
for parakeet control, eliminate a insecticide, that its effective is
the high threat, and its accumulative action is lesser than others chlorates,
its environment impact and its toxicity made inadequate its use, having
adequate substitutes, except for parakeet control.
We need to add at all the mentioned
actions the chlorate monitoring residues in stored grains destined to
internal consume as well exportation, the meat monitoring residues and
some evaluations made by analytical laboratories of the Plant Protection
Direction in certain fruits and vegetables that commercialize in the
major center of Uruguay, Model Market, has rendered to conclude that
chlorates residues do not create threat to consumers and the environment.
In the practice, since 1991, except dodecachloro and endosulfan were
no import chlorate insecticides.
Finally with the prohibition of
chlorated insecticides (except dodecachlor and endosulfan) by Ministry
Resolution dates September 23 1997 culminate regulatory actions of this
POPs that initiated in 19687 with the chlorated insecticides ban in
grasslands and prairies.
Today 1998, only are authorized
endosulfan and dodecachlor, the first without the problems of the group.
Formulation authorize of dodecachlor is granular toxic boat with 0,45%
of active ingredient for control cutting ants. This type of formulation
it is choose by the farmers for ant control in fruticulture, horticulture,
floriculture and mainly forestall cultures. This is because the farmer
saw the toxic bait granule in the ant ways to nest, and the ant’s
charge it and introduce the toxic in the colony. The others products
are formulated like dusts and concentrates and to imply it, to have
to search the nest, and to introduce the product, being more difficult
In Uruguay they are others toxic
bait granules registered at sufluramida and phenil pirazol, but this
products do not conform many of the farmers, whom continue using dodecachlor.
Today, dodecachlor is in revision
and study for Plant Protection Division of the General Direction of
Agronomic Services takes in account others alternatives. Some farmers
differ with dodecachlor ban, and they argue that the quantity of toxic
bait granulate applied is very few for ant nest to contaminate the environment
and they wish to wait until found others substitutes of the same efficient
control than dodecachlor.
In relation to a soil treatment,
actually it is used chlorpirifos, diazinon or carbofuran for example
with the same effectively than chlorate insecticides.
With respect a parakeet control,
the substitution of endrin by carbofuran, do not lessen toxicological
threat to applicators and environment, because the used formulations
(flowable 40%) is the high toxicity and no selective.
In the agromedical area, the survey
of organochlorates pesticides realized in exposed and no exposed populations
and studies in mother's milk and cord umbilical blood had detected the
problematic, and were the basis for take restrictive an ban actions.
The intoxication statistics indicate
that labor intoxication is limited. In the environmental area it is
where the effort had been less incentives, but there are papers that
show the presence of pesticides residues in rivers, but there are not
consequence of national management, because the rivers are binationals
and trinationals and the chlorates residues can be origin of neighbor
countries and no only from Uruguay.
The relative recent creation (10
years) Ministry of Dwelling, Territorial Ordering and Environment Media,
would permit, take new measures with a national regulations that will
permit increase this actions.
l. Boroukhovitch M. 1973, Reseña
sobre Insumos de Insecticidas en Uruguay para la Agricultura. Primera
Reun. CIPA -COPANT Plaguicidas - Residuos de Plaguicidas Buenos Aires.Doc
2. Boroukhovitch M. 1978, Manejo
de Plaguicidas y Preservacion del ambiente. Rev. As. Uruguaya de Seguridad,
3. Boroukhovitch M y Llanes E 1982,
Breve Reseña sobre Estadisticas y Empleo de Plaguicidas Agricolas
en Uruguay. Congreso Seguridad e Higiene en el Trabajo. As. Uruguaya
Seguridad Paysandu. Uruguay
4. Boroukhovitch M. 1988, Algunas
Acciones Realizadas a Nivel de la Direccion General de Servicios Agronomicos
en Relacion con Contaminantes en Alimentos. Primer Seminario de Ecotoxicologia/Soc
Uruguaya de Toxicol. y Ecotoxicologia Montevideo 29/30 abril 14 pp Montevideo
5. Burger,M,de Barbino J.P.,Schonbrod
P,Decia C,Boroukhovitch M and Antonaz R. 1980. Niveles Sanguineos de
Plaguicidas Organoclorados en Uruguay en Adultos Expuestos y no Expuestos.
Libro Resum. Soc. Uruguaya Toxic. y Ecotoxicol. So Congreso Latinoamericano
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