Upper normal range of urine levels

figure 65-3 The concentration of mercury vapor in the air and related concentrations of mercury in urine asso■ ciated with a variety of toxic effects.

accompanied by vomiting. The vomiting is perceived to be protective because it removes unab-sorbed mercury from the stomach; if the patient is awake and alert, vomiting should not be inhibited. The local corrosive effect of ionic inorganic mercury on the GI mucosa results in severe hematochezia with evidence of mucosal sloughing in the stool. Hypovolemic shock and death can occur in the absence of proper treatment, which can overcome the local effects of inorganic mercury.

Systemic toxicity may begin within a few hours of exposure to mercury and last for days. A strong metallic taste is followed by stomatitis with gingival irritation, foul breath, and loosening of the teeth. The most serious and frequent systemic effect of inorganic mercury is renal toxicity. Acute tubular necrosis occurs after short-term exposure, leading to oliguria or anuria. Renal injury also follows long-term exposure to inorganic mercury, where glomerular injury predominates.

Organic Mercurials

Most human toxicological data about organic mercury concern methylmercury. More than 90% of methylmercury is absorbed from the human GI tract. The organic mercurials distribute more uniformly to the various tissues than do the inorganic salts; they also cross the blood—brain barrier and the placenta and thus produce more neurological and teratogenic effects. A significant portion of the body burden of organic mercurials is in the red blood cells; for methylmercury, the red cell-plasma ratio is ~20:1. Symptoms of exposure to methylmercury are mainly neurological; Table 65-1 lists frequency of symptoms and corresponding blood levels of methylmercury. Effects of methylmercury on the fetus can occur even when the mother is asymptomatic; mental retardation and neuromuscular deficits have been observed.

Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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