Pediatric Injuries and Toxic exposures/environmental health issues

Toxicants that cross the placenta

drugs, carbon monoxide, mercury, lead, and cotinine (from environmental tobacco smoke)

Laboratory tests available to test for environmental toxins

plasma lead levels, gas-liquid chromatrography (for polychlorinated biphenylis), atomic absorption spectrometry (for mercury), carboxyhemoglobin (for carbon monoxide poisoning), 24 hour urine (for heavy metals), plasma cholinesterase levels (for pesticide metabolites, organophosphates), urinary cotinine assays (for tobacco metabolites).

Strategies to reduce exposure to outdoor air pollution

Staying indoors when outdoor air pollution levels are high and limiting outdoor activity, using portable or central air cleaning systems, avoiding areas with high levels of pollution, and using well-fitting N-95 or equivalent respirator mask when air quality is poor may be helpful.

Common poisoning agents

lead, mercury, arsenic, pesticides

Clinical manifestations of poisoning

Heart rate: bradycardia or tachycardia. Respirations: bradypnea, tachypnea. Blood pressure: hypotension, hypertension. Temperature: hypothermia, hyperprexia (differing from hyperthermia). Neurologic: central nervous system depression, including coma, agitation, delirium/psychosis, seizures, ataxia, weakness/paralysis, tremors/myoclonus, choreoathetosis, rigidity. Ophthalmologic: miosis, mydriasis, nystagmus. Dermatologic: jaundice, cyanosis, pink or red. Odors from patient: acetone (fruity), bitter almond, garlic, oil of wintergreen, gasoline, turpentine, kerosene, rotten eggs.

Lead intoxication

damage to the brain and nervous system and slowed growth and development. Children may also have learning and behavior problems and hearing and speech problems.

Mercury intoxication

mainly causes health effects when inhaled as a vapor where it can be absorbed through the lungs. Symptoms of prolonged and/or acute exposures include: tremors, emotional changes (mood swings, irritability, nervousness, excessive shyness), cognitive thinking, memory, attention, language, fine motor skills, and visual spatial skills

Arsenic intoxication

Developmental delays, neurologic problems, and an increased risk of certain cancers. Nausea, vomiting, hematemesis, diarrhea, anorexia, weight loss, bone marrow suppression, cardiac dysfunction, and sensorimotor peripheral neuropathy

Management of lead poisoning

Inform caregiver of level of toxicity, provide caregiver dietary and environmental educaiton, remove child from source, report to public health department, initiate environmental investigation (some health departments may do this), initiate lead hazard control/abatement, follow up BLL every 3 months until BLL declines, refer to social services if indicated.

Blood lead level that necessitates action

> 2 mcg/dL

BLL <3.5 mcg/dL

No considered lead poisoning: provide cargiver/parent dietary and evironmental education. Assess development, and dietary intake especially iron and calcium. Iron deficiency increases ingested lead absorption. Conduct a history of the family and child’s environment to determine if the child is exposed to a lead source (pre-1978 housing). Provide appropriate resources. Retest 12-24 months of age, 24-72 months without a history of previous screening.

BLL <3.5-19 mcg/dL

Obtain confirmatory venous level only if screening level was not venous. Report results to health department. Help arrange a home enviornmental investigation. Evaluate for iron deficiency. BLL 10-19; 1-3 months. 2.5-9; 6-9 months. 10-19; 3-6 months.

BLL 20-44 mcg/dL

Confirmatory venous blood test if screening level was not venous within 2 weeks. Consider obtaining abdominal radiograph to evaluate for chips of lead-based paint or radiopaque foreign bodies. Obtain complete history and physical with emphasis on etiology of lead exposure. Consult with poison control for further management (bowel decontamination may be needed). Early follow-up at 2 weeks-1 month, later follow-up 1-3 months.

BLL >45 mcg/dL

Confirmatory venous blood test if screening level was not venous within 48 hours. Perform complete history and physical with thorough neurologic exam. Obtain abdominal radiogrpah, if needed. Initiate bowel decontamination. Obtain CBC, electrolytes, BUN, creatinine, liver transaminase enzyme levels, and a urinalysis. Consider admission to hospital if unable to find a safe lead free environment. Hospitalize immediately for signs of lead toxicity: nausea, abdominal pain, confusion, weakness, coma, and/or seizures. Consult a medical toxicologist for further management. Contact poison control. Follow-up BLLs are recommended as soon as possible