[3] Since 1998, risk assessment studies have been conducted by (among others) the EPA (United States Environmental Protection Agency).

[5] Ethion is produced under controlled pH conditions by reacting dibromomethane with Diethyl dithiophosphoric acid in ethanol.

[6] Ethion monoxon is an inhibitor of the neuroenzyme cholinesterase (ChE), which normally facilitates nerve impulse transmission; secondary damage thus occurs in the brain.

The phosphorylated form of the enzyme is highly stable, and depending on the R and R′ groups attached to phosphorus, this inhibition can be either reversible or irreversible.

[8] Goats exposed to ethion showed clear distinctions in excretion, absorption half-life and bioavailability.

In a representative study, liver, muscle, and fat tissues were examined after 10 days of ethion exposure.

[8] The subsequent step in the biotransformation process is not yet completely known, yet it is understood that this happens via esterases in the blood and liver (1).

After identification of the 14C residues in organs of the goats, such as the liver, heart, kidneys, muscles and fat tissue, it appeared that 0.03 ppm or less of the 14C compounds present was non-metabolized ethion.

Severe poisoning might lead to fatigue, involuntary muscle contractions, loss of reflexes and slurred speech.

[6] When being exposed through skin contact, the lowest dose to kill a rat was found to be 150 mg/kg for males and 50 mg/kg for females.

[6] When being exposed through ingestion, 10 mg/kg/day and 2 mg/kg/day showed no histopathological effect on the respiratory track of rats, nor did 13-week testing on dogs (8.25 mg/kg/day).

[6] According to Extoxnet,[14] any form of exposure could result in the following symptoms: pallor, nausea, vomiting, diarrhea, abdominal cramps, headache, dizziness, eye pain, blurred vision, constriction or dilation of the eye pupils, tears, salivation, sweating, and confusion may develop within 12 hours.

Severe poisoning may result in distorted coordination, loss of reflexes, slurred speech, fatigue and weakness, tremors of the tongue and eyelids, involuntary muscle contractions and can also lead to paralysis and respiratory problems.

In rabbits receiving 250 mg/kg of technical-grade ethion for 21 days, the dermal exposure lead to increased cases of erythema and desquamation.

In guinea pigs, ethion ALS lead to a slight erythema that cleared in 48 hours, and it was determined that the compound was not a skin sensitizer.

Skin contact with organophosphates, in general, may cause localized sweating and involuntary muscle contractions.

[6][14] A six-month-old boy experienced shallow excursions and intercostal retractions after accidentally ingesting 15.7 mg/kg ethion.

The same boy also showed occurrence of tachycardia, frothy saliva (1 hour after ingestion), watery bowel movements (90 minutes after ingestion), increased white blood cell counts in urine, inability to control his head and limbs, occasional twitching, pupils non-reactive to light, purposeless eye movements, palpable liver and spleen, and there were some symptoms of paralysis.

In a group of six male volunteers no differences in blood pressure or pulse rate were noted, neither in mice or dogs.

Diarrhea did occur in mice orally exposed to ethion, severe signs of neurotoxicity were also present.

In a 90-day study on dogs, in which the males received 6.9 mg/kg/day and the females 8.25 mg/kg/day, ataxia, emesis, miosis, and tremors were observed.

Based on these findings, a minimal risk level of 0,002 mg/kg/day for oral exposure for acute and intermediate duration was established.

In a study on pregnant river rats, eating 2.5 mg/kg/day, it was observed that the fetuses had increased incidence of delayed ossification of pubes.

Another study found that the fetuses of pregnant rabbits, eating 9.6 mg/kg/day had increased incidence of fused sterna centers.

As stated earlier, ethion can also lead to pupillary constriction, muscle cramps, excessive salivation, sweating, nausea, dizziness, labored breathing, convulsions, and unconsciousness.

Ethion has not been classified for carcinogenicity by the United States Department of Health and Human Services (DHHS), the International Agency for Research on Cancer (IARC) or the EPA.

Safety guidelines also encourage to induce vomiting to reduce oral exposure, if the victim is still conscious.

The main danger lies in respiratory problems - if symptoms are present, then artificial respiration with an endotracheal tube is used as a treatment.

When looking at larger, upland game birds (like the ring-necked pheasant and waterfowl like the mallard duck, ethion varies from barely toxic to nontoxic.

In a recently introduced method, the interaction of silver nanoparticles (AgNPs) with ethion results in the quenching of the resonance relay scattering (RRS) intensity.