saturnismo

Definition of saturnism

Saturnism indicates a serious organic and metallic lead intoxication, a poisoning in all respects triggered by the continuous and assiduous exposure of the subject to this mineral. Saturnism is caused by contact, inhalation or absorption of lead through the mucous membranes, the skin or the gastro-enteric apparatus.

The term "saturnism" comes from "Saturn", a name that alchemists attributed to lead.

Saturnism and madness

In the past, it was customary to sweeten wine with lead salts: this unusual practice caused a progressive accumulation of lead in the body, which was reflected in abnormal and schizophrenic behaviors, which perfectly outlined madness, typical of saturnism.

The folly of the Ancient Romans seems to be due precisely to saturnism: the Ancients not only softened the wine with lead oxides, but also preserved it in lead barrels; the acidity of the wine was held responsible for the dissolution of the lead oxide which, from the container, passed into wine.

Many painters, such as Van Gogh and Goya, used to use lead-based colors for the realization of their works; madness, schizophrenia and mental and psychological disorders of the same were attributed to lead intoxication, caused precisely by inhalation and ingestion of colors (the sources report that Goya used to wet the tip of the brush with the saliva, not with water, ingesting large quantities of lead that accumulated in the body).

Causes and risk factors

Saturnism is a widespread phenomenon among those workers who are in contact with lead or its derivatives every day: the workers involved in welding, the production of paints, the painting of ceramics, the production of batteries, and the subjects who they are often in contact with firearms representing the categories most at risk of poisoning.

Lead fusion workers probably belong to the group of workers most exposed to progressive lead poisoning: just think that at a temperature of 450/500 ° C, lead vapors far exceed the minimum tolerable concentration in the atmosphere (0.15 mg lead / m3).

However, lead poisoning does not only affect the categories of workers described above, but may also depend on environmental factors outside work:

• The pollution of the water induced by old lead pipes and the subsequent ingestion of the same, could favor the accumulation of lead in the body;
• The residue of lead pesticides present in some flours could cause poisoning;
• The clandestine production and the consumption of super alcoholic distillates, clarified with lead salts or preserved in lead containers, represent other factors that could favor saturnine madness;
• The pollution caused by the exhaust gases of some non-regulated cars could release some lead residues in the atmosphere, which are deposited in the body following continuous inhalation;
• Soils polluted by lead could also contaminate plants, especially broad-leaf vegetables: excessive ingestion of these vegetables causes the accumulation of lead in the body;
• Hunting pellets and bullets in general, if not removed from the body, could favor the accumulation of lead in the body, thus causing long-term poisoning and death from progressive lead poisoning.

Effects

By definition, the saturnism is a chronic lead poisoning, therefore generally we do not speak of an acute form; however, acute (pseudo) poisoning involves haemolytic anemia, nausea, vomiting, very severe abdominal pain, convulsions, mental disorders and kidney failure: the symptoms that derive from the "acute" form of saturnism do not differ greatly from the intoxications generally speaking.

Acute poisoning is almost improbable in subjects involved in the processing of lead in general, while it is possible in cases of voluntary or less excessive doses of lead.

Unfortunately, the inevitable consequence of this rare form of saturnism is death.

The chronic form of saturnism causes symptoms at the level of the various districts:

• Central nervous system: saturnine encephalopathy, paralysis, cerebral edema;
• Bone-muscular system: acute gout, bone and cartilage lesions, arthrosis and pain in the limbs;
• Gastrointestinal system: lack of appetite, nausea, vomiting, Burton's hollow (thin bluish-colored layer that affects the gum below canines and incisors, typical lead poisoning light), colic, constipation;
• Circulatory system: alteration of arterial pressure values, gangrene;
• Renal system: gouty nephropathy, renal failure, oliguria (decrease in urinary volume);
• Hematopoietic system: anemia;
• Reproductive system: in humans, poisoning can cause spermatic alterations (eg oligospermia), while in women infertility.

Furthermore, the saturnism causes an alteration of the taste of foods, a perception of "metallic" taste, a noticeable thirst, anorexia, anxiety, headache, tremor, mental disorders, lack of motor coordination and "madness".

Precise lethal dose of lead

The sensitivity of each person to lead is variable, so it is very difficult to accurately quantify the lethal dose of lead (DL: 50% lethal dose); however, it is estimated that the lethal dose of lead absorbed in the adult is around 0.5 grams / kg (which corresponds to about 10 grams of soluble lead salts ingested).

Toxic action of lead

At the gastric level, lead is transformed into lead chloride (soluble), then it passes into the blood and plasma in the form of phosphate: lead phosphate binds to erythrocytes, heading towards the bones, liver and spleen (tissues and target organs of lead). Lead is eliminated through feces and urine, but in excessive doses it accumulates, bringing back the toxic action (saturnism). Probably, the deposition of lead inhibits the synthesis of proteins and enzymes, but the mechanism of the toxic in the organism is still object of study for many researchers.

Treatment for saturnism

First, subjects suffering from saturnism must leave the source of exposure; secondly, the doctor prescribes the administration of a chelating substance, capable of sequestering the lead accumulated in the body. The antidote is the CaNa ₂ EDTA salt, administered intravenously: the therapy must be repeated for a few days, spacing suspensions and resumed until reaching the ideal lead (index of the amount of lead in the blood).

In the case of acute lead poisoning, the treatment against saturnism also involves subjecting the patient to gastric lavage; among the possible complementary therapies, penicillin, succimer (meso-2, 3-dimercaptosuccinic acid) and dimercaprol also stand out.

To alleviate the symptoms of saturnism, the doctor generally prescribes spasmolytics and drugs aimed at correcting blood pressure.

Summary

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