By Jorge Hern�n Botero Tob�n, M.D.
Consultant on Chemical Safety, Human Health and the Environment
September 19, 2002
In addition to the challenges inherent in the problem, police work to eradicate illegal crops in Colombia through aerial fumigation with glyphosate faces an avalanche of adverse public opinion due to disinformation from the media on the supposedly toxic effect of glyphosate on humans, animals and other environmental components. This is speculation and ignores the basic facts of public health.
As to the only agent used; that is, N-phosphonomethylglycine or glyphosate, there is a host of basic scientific research to support its limited toxicity to humans, animals and environmental tracer species, as well as its benevolence to the abiotic environment. A number of scientific studies also rule out the presence of undesirable properties with respect to its behavior in the ecosystem and its fate in the environment.
At any rate, keeping an eye on the possible risks posed by this activity helps to improve its image and to specify any possible undocumented or undescribed effects of the substance under the conditions in which it is applied.
The purpose of this report is to provide technical elements and scientific evidence for an analysis of how the glyphosate mixture used to destroy illegal crops might have affected the health of children in Puerto As�s (Putumayo).
2. BACKGROUND INFORMATION
A complaint filed by the Putumayo Indian Organization maintains that "children and elderly people with serious problems due to glyphosate sprayed on illegal crops have been treated at the hospital in Puerto As�s." The purpose of the visit was to verify the cause and to evaluate the medical records, if deemed appropriate.
3. PROCEDURES CARRIED OUT
A commission including an Anti-narcotics Police official, the NAS Program Officer from the United States Embassy in Bogot� and the author of this report traveled to the town of Puerto As�s (Putumayo), where the members of the commission met with the Medical Director and the Assistant Scientific Director of San Francisco de As�s Hospital in Puerto As�s (Putumayo).
The relevant aspect of the meeting was that neither the medical professionals in question nor the hospital itself had issued any sort of statement to the effect that aerial spraying with the glyphosate and water mixture used to eradicate illicit crops in the region might somehow be related to the health problems observed in the local population. Also, the frequent cases of poisoning treated at the hospital are clear enough to be attributed to specific agents other than glyphosate.
The medical director of the hospital said the Putumayo Health Department is carrying out an epidemiological study of cases suspected to be the result of aerial spraying with glyphosate in the towns of San Miguel, Puerto As�s, La Hormiga and Villa Garz�n. It is being conducted under the direction of Diva Revelo and according to a protocol designed for this purpose. The hospital will define its position based on the findings of the study.
At the time of the meeting, the commission was informed of two cases involving children who were hospitalized with clinical symptoms which family members attributed to fumigation with glyphosate. These cases were reviewed as described herein.
4. INFORMATION ON THE PATIENT'S CASE HISTORY AND EXAMINATION
Edgar Fernely Santamar�a Toro is a 13-year-old boy from the Caribe sector of the Santa Ana judicial district in Puerto As�s. His affliction evolved over a period of approximately 24 hours, beginning with abdominal pain and five episodes of vomiting, followed by the appearance, more or less 14 hours earlier, of abnormal movement in the limbs and the respiratory muscles.
An examination showed the patient was confused, awake, in apparently good general condition, but with obvious involuntary fasciculus movement of moderate to severe intensity in the limbs, thorax, abdomen and face. Vital signs: cardiac frequency-60/min., respiratory frequency - 20/min. and temperature 36 � C.
His pupils were reactive, in an intermediate position, and mucus was moist. There was no evidence of lesions. The rest of the clinical examination was normal for the child's age.
The pediatrician at the hospital indicated this was obviously a case of organophosphate poisoning (when questioned, the patient had no idea of contact or exposure). The child was also said to have responded partially to treatment with atropine, loratadine and hydration administered orally.
The author of this report agrees with the diagnosis and recommends the addition of diphenhydramine, in the amount of 6 mg/kg/day divided into three doses to prevent occurrence of the intermediate syndrome, plus reduction of the dose and abbreviation of the duration of treatment with atropine.
Michele Guerrero is a three-year-old girl from the village of Canad� in the San Miguel municipal district. Her condition initiated eight days earlier, with a moist cough, clear nasal secretion and no fever. These symptoms worsened the day before hospitalization, when she began to have serious difficulty breathing. The child had never before experienced an aliment with these characteristics. The family mentioned there were several aerial spayings in the village prior to the onset of her illness.
An examination found her to be conscious, alert and hydrated with intravenous liquids. She was crying moderately and had moderate difficulty breathing. Vital signs: cardiac frequency 120/min., respiratory frequency 40/min. and temperature 37� C.
The pediatrician noted her clinical symptoms had improved with the administration of hydrocortisone, theophylline and inhaled beclomentasone. This supports a clear diagnosis of bronchial asthma, specifically an initial episode.
CLINICAL ANALYSIS OF THE SITUATION
What is involved in this situation is an attempt to attribute these cases to the supposed negative and undesirable human health effects of spraying with the glyphosate and water mixture used to eradicate illegal crops in the area. This demonstrates the arbitrary way these effects are attributed to the commercial formulation of glyphosate being used.
In case no. 1, for example, the clinical symptoms are clearly indicative of organophosphate poisoning. By inhibiting an enzyme in the nervous system known as cholinesterase, organophosphates cause the signs and symptoms observed in the patient. In this instance, there is no documentation of exposure to an organophosphate substance. It may be that such substances are stored and handled in unsafe conditions on the farm where the boy lives.
In the case of the girl, also with a clear and very different diagnosis of what could have induced exposure to glyphosate, local spraying is cited as the cause, even though the onset of her ailment, in time with the spraying, is spurious and the product of chance.
In fact, human exposure to glyphosate formulations is manifest after sizable quantities of the concentrated commercial product are ingested, usually in excess of 150 mL. Such manifestations are mainly gastrointestinal (abdominal pain, nausea, vomiting and diarrhea). The girl's bronchial spasm, which has improved with specific treatment for bronchial asthma, has nothing to do with any eventual exposure to glyphosate or to another chemical substance.
Environmental Health Criteria No. 159, Glyphosate, International Programme on Chemical Safety, Geneva, 1994
Her response to specific treatment for bronchial asthma, which in essence contains no other anti-toxic measure, completely rules out chemical exposure as the possible cause in this case.
It is, therefore, important to point out the phenomenon characterized as "perceived risk and sense of illness" (according to Hern�n de San Mart�n), whereby individuals and communities always tend to attribute the onset of illness to any extraordinary event outside the realm of daily circumstance.
Naturally, and according to the same author, perceived risk and sense of illness only have overall indicative and orienting value on successive studies of morbidity.
San Mart�n, H., Ecolog�a Humana y Salud, 2nd Edition, 1983, La Prensa M�dica Mexicana, Mexico.
Another factor to bear in mind is the use of highly toxic pesticides to protect coca crops in the region, and the potential for these substances to be transported by elements in the environment, subsequent to their application. At a given time, this can result in considerable exposure to humans, which would initially affect those who are most vulnerable, such as children and the elderly, in addition to certain species of wildlife, as could have happened in this case.
Nevertheless, this last variable cannot be analyzed as part of this study, since the distance between occurrence of these clinical events, their notification and the need for their investigation offer no possibility of the environmental epidemiological research required to examine them.
The ideal, in the event of future health complaints, would be to access the program sites immediately for a more precise diagnosis. However, local security conditions and logistics make immediate attention and analysis difficult.
In the first case analyzed, the patient's affliction is attributable to a toxic cause, even without any notion of exposure. The symptoms are sufficiently clear and point to inadvertent skin exposure to a toxic agent (pesticide), quite likely an organophosphate, possibly related to the domestic storage and handling of a pesticide under precarious conditions. The symptoms are obvious in this respect, and the attending pediatrician fully agrees with this opinion.
For example, in spite of having a phosphorous atom in its molecule, glyphosate does not act as an organophosphate substance inhibiting the cholinesterase enzyme in the nervous system. In terms of biological action, it specifically inhibits the enolpyruvyl-shikimate phosphate synthase enzyme, which is exclusive to plants. This is a proven fact. Therefore, it is impossible to attribute the boy's case to any eventual exposure to glyphosate or to the mixture used in the eradication program, regardless of the amount.
In the second case, the girl's ailment is plainly restricted to the respiratory tract and does not fit any described clinical symptom of poisoning. This coincides with the opinion of the specialist who is treating the child.
In both cases, there is clearly no cause and effect relationship between aerial spraying through the eradication program and the health problems of the two patients.