Pesticide poisoning

Pesticides are chemicals designed to protect crops from various pests and diseases. But are they really safe for humans? Experience shows that the danger of pesticide poisoning does exist, and the intoxication can be quite strong, and the consequences can be serious. So how harmful are pesticides, and what to do if you are poisoned by these chemicals?

Epidemiology

Over the past ten years, the use of toxic chemicals in agriculture has decreased somewhat, but pesticide poisoning still occupies one of the leading places among all chemical intoxications. Most often, mass pesticide poisoning is recorded, which is especially relevant for developing countries. For example, in Nicaragua, 80% of pesticide poisonings are of a mass professional nature.

On average, among all poisonings, pesticide damage accounts for approximately 12%, which is not a small number. Poisonings are recorded mainly in rural areas. [ 1 ]

Causes pesticide poisoning

Depending on the cause, pesticide poisoning is divided into professional and domestic.

• Professional poisonings include those that occur among those who work in pesticide manufacturing plants, seed treatment plants, or field and gardening enterprises. Poisonings can occur during maintenance of processing equipment, accidental release of pesticides, or consumption of food or water containing traces of toxic substances. Intoxication can also develop when working with processed plants – for example, if a gardener is pruning, weeding, etc. However, in most patients with professional pesticide poisonings, the cause is non-compliance with safety regulations – for example, if work is performed without the use of personal protective equipment. Rules for the transportation and storage of chemical reagents are often violated, and the time limits for visiting processed gardens and fields are not observed.
• Household poisoning is typical among people who do not have professional contact with pesticides. For example, many summer residents incorrectly store chemicals in living quarters, where they can easily be confused with something else and used for other purposes. In addition, there are frequent cases of using pesticide containers to store food products, which is absolutely unacceptable. And some gardeners cultivate their land without observing safety regulations. All this can lead to severe pesticide poisoning. [ 2 ]

Risk factors

The following groups of the population are most susceptible to pesticide poisoning:

• workers in the chemical and agricultural industries;
• summer residents, gardeners, vegetable growers;
• children and elderly people.

Poisonings are most often accidental rather than intentional. The following factors aggravate the clinical picture:

• chronic diseases, recent surgeries;
• young age of the victim;
• alcoholism;
• frequent stress, malnutrition, mental illness. [ 3 ]

Pathogenesis

Pesticides are a collective term that denotes chemical compounds of different compositions that can protect crops and animals from diseases and pests. The use of such substances is technically simple, they are inexpensive and quite effective, so they are often used by both professional agricultural and farming organizations and ordinary amateur gardeners.

Pesticides are many chemical compounds that differ in structure and direction of action. Today, several of their classifications are known:

• insectoacaricides – agents that affect harmful insects;
• nematicides - pesticides for killing worms;
• rodenticides – agents directed against rodents;
• herbicides – agents that destroy weeds, etc.

According to their chemical structure, pesticides can be organochlorine, mercury-containing, arsenic, phenol-containing, organophosphorus, etc.

Conventional dilutions of preparations recommended for processing are considered low-toxic, low-stable, and do not have cumulative properties. However, acute, subacute, or chronic poisoning may develop when pesticides directly enter the human body. At the same time, any dose of pesticides has xenobiotoxic properties and can cause certain disorders in the body.

The main mechanism of toxic influence is the reaction of stimulation of free radical processes, which are regulated by the antioxidant system. The stability of functional and structural indicators of biological membranes is disrupted, which leads to disruption of the structural and functional organization of cells. In general, such changes cause a failure in the systemic functioning of the body, in the course of adaptive and protective reactions, which entails the development of immunodeficiency states. [ 4 ]

Symptoms pesticide poisoning

Signs of mild acute pesticide poisoning include headache, dizziness, weakness in the arms and legs, sudden deterioration of vision, dyspepsia, and increased salivation. Patients are usually restless and anxious. Examination reveals pupil constriction, insufficient response to light stimuli, increasing spasm of accommodation, and deterioration of adaptation to darkness. Nystagmus is observed with extreme abduction of the eyeballs, facial puffiness, and hyperhidrosis.

The first signs do not appear immediately, as pesticide poisoning manifests itself in certain stages:

• the latent stage, which lasts from the moment of intoxication until the first visible symptoms, and can last from a couple of hours to several days;
• precursor stage – characterized by signs of non-specific poisoning (nausea, periodic vomiting, weakness and fatigue, headache);
• the stage of increasing intoxication (specific signs of pesticide poisoning appear).

A subacute pathological condition is characterized by a weak reaction of the body to toxic effects and a longer intoxication process. Although children and weakened patients may be more sensitive to toxic substances.

Chronic poisoning is characterized by persistent headaches (usually in the temples), general heaviness, dizziness, memory loss, sleep and appetite disorders, nausea, and decreased performance. Bradycardia and decreased blood pressure are often recorded. Some patients have disorders of the biliary system, gastric secretion is impaired, and allergic reactions such as dermatitis and bronchitis often occur. [ 5 ]

Complications and consequences

The consequences of intoxication depend on many factors:

• from the amount of poison that has entered the body;
• from the degree of fullness of the stomach (if the poison was swallowed);
• on how quickly first aid was provided to the victim.

In general, the consequences may be as follows:

• deterioration of vision, damage to the optic nerve;
• paresis, paralysis of arms and legs;
• stomach ulcer;
• toxic liver damage;
• acute pancreatitis;
• development of psychoses and other disorders of the nervous system;
• acute respiratory failure;
• cardiac insufficiency;
• acute renal failure;
• encephalopathy;
• coma;
• death of the patient.

Severe pesticide poisoning is accompanied by a comatose state. In a deep coma, the victim loses sensitivity, tendon reflexes are lost, muscle hypotension, and blood pressure drops. If no assistance is provided, the person may die. [ 6 ]

Diagnostics pesticide poisoning

All patients admitted to hospital with pesticide poisoning are given a general clinical examination, which includes:

• blood and urine tests, blood biochemistry;
• electrocardiography, ultrasound examination of the abdominal cavity and chest organs;
• chest x-ray;
• electroencephalography.

General clinical biochemical diagnostics involves assessing the functional capacity of the kidneys and liver using standard accepted methods.

Auscultation of the respiratory organs reveals harsh breathing and dry wheezing. The cardiovascular system demonstrates tachycardia, turning into bradycardia. Heart sounds are muffled, the electrocardiogram shows a noticeable prolongation of the PQ interval, reduced P and T waves, indicating initial suppression of the sinus node. Changes in the electrocardiogram are present for a week from the moment of pesticide poisoning.

Electroencephalography allows us to detect moderately altered background activity, which manifests itself in a disruption in the organization of basic brain activity.

Laboratory tests show a decrease in oxygen concentration in the blood, a deviation towards acidosis, a lack of potassium, symptoms of increased blood clotting, and a decrease in cholinesterase activity.

Differential diagnosis

Differential diagnostics are appropriate with other anticholinesterase intoxications - first of all, poisoning with drugs is considered: Proserin, Pilocarpine, Galantomine. When differentiating, it is necessary to take into account that the voiced drugs transiently inhibit cholinesterase, so their activity is easily inhibited by atropine. In case of pesticide poisoning, the effect of the poisons is present for a long time, and atropine acts only after several anticholinergic injections.

In addition, intoxication is differentiated from pulmonary edema, acute appendicitis and peritonitis, and acute cerebrovascular accident. [ 7 ]

Treatment pesticide poisoning

In case of pesticide poisoning, non-specific detoxification therapy should be provided within the first 1-2 hours from the onset of intoxication, including a copious shower with a detergent, the use of saline laxatives, and a gastric lavage procedure followed by taking a sorbent drug. It is recommended to drink a large volume of alkaline water (up to two or three liters per day): simultaneously take diuretics, infuse rheopolyglucin (or rheosorbilact, up to 400 ml per day), and conduct symptomatic treatment.

In case of severe poisoning, a solution of sorbitol or magnesium sulfate (25 g per glass of water three times a day) is prescribed during the first 48 hours, which leads to the development of osmolar diarrhea.

In acute pesticide poisoning, the antidote is 0.1% atropine sulfate, which is administered in a quantity of 1-2 ml. It is possible to re-administer the antidote at half-hour intervals until the signs of cholinergic syndrome disappear.

Severe poisoning requires additional administration of cholinesterase reactivators:

• 15% dipyroxime bromide 1 ml intravenously or intramuscularly up to three times a day with a minimum interval of 1 hour;
• 10% dietixim 1-2 ml during the first two days.

Emergency administration of drugs is usually not accompanied by clinically significant side effects. However, the possibility of an allergic reaction cannot be ruled out. If this happens, urgent measures are taken to replace the drug with another pharmacological analogue.

On the second day, additional diagnostics are carried out to determine whether there are any disturbances in the body's basic functions.

First Aid for Pesticide Poisoning

First aid begins with emergency blocking of the toxic substance from entering the body. If necessary, use a respirator or gas mask, remove the victim from the area of the toxic chemical. Remove clothing, treat exposed areas of the body with a 5% ammonia solution or plain water.

If the pesticide solution was swallowed, the stomach and intestines should be cleaned out immediately:

• induce vomiting by first drinking several cups of water and one cup of water with a small amount of soap dissolved in it;
• give the victim a laxative (any, except castor oil).

After cleansing the stomach and intestines, give the patient a glass of milk or oatmeal broth, ensure a lying position and rest. If the victim complains of weakness, you can offer him a cup of strong coffee without sugar.

An ambulance must be called, or the person must be urgently transported to the hospital emergency department. [ 8 ]

Prevention

Preventive measures to avoid pesticide poisoning include the following recommendations:

• If your professional activity involves the production, packaging or transportation of pesticides, you must use all necessary personal protective equipment, wash your hands and face frequently, rinse your mouth, and avoid direct contact with chemicals.
• It is important to ensure proper storage of pesticides – in tightly sealed containers, with labeled stickers, in places inaccessible to children, the elderly and mentally unstable people, away from living quarters. The storage area should be well ventilated and have no potential sources of ignition.
• When handling or diluting pesticides, make sure there are no people nearby, especially children. Do not forget about safety precautions.
• If you have any suspicions of pesticide poisoning, you should seek medical help as soon as possible – from a toxicologist, epidemiologist, or infectious disease specialist.

Forecast

Pesticides are quite dangerous toxic substances. However, in agriculture and the agricultural sector, it is quite difficult to grow a good harvest without them. Therefore, if all safety measures are observed, these chemicals do not pose a danger to humans. Nevertheless, pesticide poisoning is quite common. We are talking about a painful condition caused by the ingestion of pesticides. Most often, acute poisoning is recorded, requiring emergency medical intervention.

Before the doctors arrive, first aid should be provided by the immediate environment of the victim. The prognosis for the patient's life and health largely depends on this. If the aid was provided in a timely and complete manner, then pesticide poisoning can be cured without any negative consequences for the body.