Poisoning occurs when any substance interferes with normal body functions after it is swallowed, inhaled, injected, or absorbed. Poisonings are a common occurrence. About 10 million cases of poisoning occur in the United States each year. In 80% of the cases, the victim is a child under the age of five. About 50 children die each year from poisonings. Curiosity, inability to read warning labels, a desire to imitate adults, and inadequate supervision lead tochildhood poisonings.
The elderly are the second most likely group to be poisoned. Mental confusion, poor eyesight, and the use of multiple drugs are the leading reasons why this group has a high rate of accidental poisoning. A substantial number of poisonings also occur as suicide attempts or drug overdoses.
Poisons are common in the home and workplace, yet there are basically two major types. One group consists of products that were never meant to be ingestedor inhaled, such as shampoo, paint thinner, pesticides, houseplant leaves, and carbon monoxide. The other group contains products that can be ingested insmall quantities, but which are harmful if taken in large amounts, such as pharmaceuticals, medicinal herbs, or alcohol. Other types of poisons include the bacterial toxins that cause food poisoning, such as Escherichiacoli; heavy metals, such as the lead found in the paint on older houses;and the venom found in the bites and stings of some animals and insects. Thestaff at a poison control center and emergency room doctors have the most experience diagnosing and treating poisoning cases.
The effects of poisons are as varied as the poisons themselves; however, theexact mechanisms of only a few are understood. Some poisons interfere with the metabolism. Others destroy the liver or kidneys, such as heavy metals and some pain relief medications, including acetaminophen (Tylenol) and nonsteroidal anti-inflammatory drugs (Advil, Ibuprofen). A poison may severely depressthe central nervous system, leading to coma and eventual respiratory and circulatory failure. Potential poisons in this category include anesthetics (forexample, ether and chloroform), opiates (for example, morphine and codeine),and barbiturates. Some poisons directly affect the respiratory and circulatory system. Carbon monoxide causes death by binding with hemoglobin that wouldnormally transport oxygen throughout the body. Certain corrosive vapors trigger the body to flood the lungs with fluids, effectively drowning the person.Cyanide interferes with respiration at the cellular level. Another group of poisons interferes with the electrochemical impulses that travel between neurons in the nervous system. Yet another group, including cocaine, ergot, strychnine, and some snake venoms, causes potentially fatal seizures.
Severity of symptoms can range from headache and nausea to convulsionsand death. The type of poison, the amount and time of exposure, and the age,size, and health of the victim are all factors which determine the severityof symptoms and the chances for recovery.
There are more than 700 species of poisonous plants in the United States. Plants are second only to medicines in causing serious poisoning in children under age five. There is no way to tell by looking at a plant if it is poisonous. Some plants, such as the yew shrub, are almost entirely toxic: needles, bark, seeds, and berries. In other plants, only certain parts are poisonous. Thebulb of the hyacinth and daffodil are toxic, but the flowers are not; whilethe flowers of the jasmine plant are the poisonous part. Moreover, some plants are confusing because portions of them are eaten as food while other partsare poisonous. For example, the fleshy stem (tuber) of the potato plant is nutritious; however, its roots, sprouts, and vines are poisonous. The leaves oftomatoes are poisonous, while the fruit is not. Rhubarb stalks are good to eat, but the leaves are poisonous. Apricots, cherries, peaches, and apples allproduce healthful fruit, but their seeds contain a form of cyanide that cankill a child if chewed in sufficient quantities. One hundred mg of moist, crushed apricot seeds can produce 217 mg of cyanide.
Common houseplants that contain some poisonous parts include:
- Dumbcane (also called Diffenbachia)
Common outdoor plants that contain some poisonous part include:
- Bird of paradise flower
- Castor bean
- English ivy
- Horse chestnut
- Jimsonweed (also called thornapple)
- Morning glory
- Nightshade (several varieties)
- Sweet pea
Symptoms of plant poisoning range from irritation of the skin or mucous membranes of the mouth and throat to nausea, vomiting, convulsions, irregular heartbeat, and even death. It is often difficult to tell if a person has eaten apoisonous plant because there are no tell-tale empty containers and no unusual lesions or odors around the mouth.
Many products used daily in the home are poisonous if swallowed. These products often contain strong acids or strong bases (alkalis). Toxic household cleaning products include:
- Dishwashing liquids
- Drain openers
- Floor waxes and furniture polishes
- Laundry detergents, spot cleaners, and fabric softeners
- Oven cleaners
- Toilet bowl cleaners
Personal care products found in the home can also be poisonous. These include:
- Hair straighteners
- Nail polish and polish remover
Signs that a person has swallowed one of these substances include evidence ofan empty container nearby, nausea or vomiting, and burns on the lips and skin around the mouth if the substance was a strong acid or alkali. The chemicals in some of these products may leave a distinctive odor on the breath.
Both over-the-counter and prescription medicines can help the body heal if taken as directed. However, when taken in large quantities, or with other drugswhere there may be an adverse interaction, they can act as poisons. Drug overdoses, both accidental and intentional, are the leading cause of poisoning in adults. Medicinal herbs should be treated like pharmaceuticals and taken only in designated quantities under the supervision of a knowledgeable person.Herbs that have healing qualities when taken in small doses can be toxic in larger doses.
Drug overdoses cause a range of symptoms, including excitability, sleepiness,confusion, unconsciousness, rapid heartbeat, convulsions, nausea, and changes in blood pressure. The best initial evidence of a drug overdose is the presence of an empty container near the victim.
People can be poisoned by fumes they inhale. Carbon monoxide is the most common form of inhaled poison. Other toxic substances that can be inhaled include:
- Farm and garden insecticides and herbicides
- Gasoline fumes
- Insect repellent
- Paint thinner fumes
Initially, poisoning is suspected if the victim shows changes in behavior andsigns or symptoms previously described. Evidence of an empty container or information from the victim are helpful in determining exactly what substance has caused the poisoning. Some acids and alkalis leave burns on the mouth. Petroleum products, such as lighter fluid or kerosene, leave a distinctive odoron the breath. The vomit may be tested to determine the exact composition ofthe poison. Once hospitalized, blood and urine tests may be done on the patient to determine his metabolic condition.
Treatment for poisoning depends on the poison swallowed or inhaled. Contacting the poison control center or hospital emergency room is the first step in getting proper treatment. The poison control center's telephone number is often listed with emergency numbers on the inside cover of the telephone book, orit can be reached by dialing the operator. The poison control center will ask for specific information about the victim and the poison, then give appropriate first aid instructions. If the patient is to be taken to a hospital, a sample of vomit and the poison container should be taken along, if they are available.
Most cases of plant poisoning are treated by inducing vomiting, if the patient is fully conscious. Vomiting can be induced by taking syrup of ipecac, an over-the-counter product available at any pharmacy.
For acid, alkali, or a petroleum product poisonings, the patient should not vomit. Acids and alkalis can burn the esophagus if they are vomited, and petroleum products can be inhaled into the lungs during vomiting, resulting in pneumonia.
Once under medical care, doctors have the option of treating the patient witha specific remedy to counteract the poison (antidote) or with activated charcoal to absorb the substance inside the patient's digestive system. In some instances, pumping the stomach may be required. Medical personnel will also provide supportive care as needed, such as intravenous fluids or mechanical ventilation.
The outcome of poisoning varies from complete recovery to death, and dependson the type and amount of the poison, the health of the victim, and the speedwith which medical care is obtained.
Most accidental poisonings are preventable. The number of deaths of childrenfrom poisoning has declined from about 450 per year in the 1960s to about 50each year in the 1990s. This decline has occurred mainly because of better packaging of toxic materials and better public education.