What is the safe level of exposure to benzene?

What is the safe level of exposure to benzene?

NIOSH: The recommended airborne exposure limit (REL) is 0.1 ppm averaged over a 10-hour workshift and 1 ppm, not to be exceeded during any 15-minute work period. ACGIH: The threshold limit value (TLV) is 0.5 ppm averaged over an 8-hour workshift and 2.5 ppm as a STEL (short-term exposure limit).

What does distribution coefficient indicate?

The distribution coefficient is defined as the concentration of solute in the organic solvent divided by the concentration of solute in the aqueous phase.

What are the effects of benzene exposure?

(Long-term exposure means exposure of a year or more.) Benzene causes harmful effects on the bone marrow and can cause a decrease in red blood cells, leading to anemia. It can also cause excessive bleeding and can affect the immune system, increasing the chance for infection.

How long does benzene stay in the air?

Brief exposure (5–10 minutes) to very high levels of benzene in air (10,000–20,000 ppm) can result in death. Lower levels (700–3,000 ppm) can cause drowsiness, dizziness, rapid heart rate, headaches, tremors, confusion, and unconsciousness.

How poisonous is benzene?

Benzene is very poisonous. Poisoning can cause rapid death. However, deaths have occurred as long as 3 days after the poisoning.

What should you do if benzene is spilled or leaked?

Steps to be taken if the material is released or spilled. As much benzene as possible should be absorbed with suitable materials, such as dry sand or earth. That remaining must be flushed with large amounts of water. Do not flush benzene into a confined space, such as a sewer, because of explosion danger.

What is distribution coefficient in extraction?

The distribution coefficient is the ratio of the concentration of solute in the organic phase over the concentration of solute in the aqueous phase (the V-terms are the volume of the phases).

Is distribution coefficient constant?

When you put liquid sample in a vial, the analyte evaporates from liquid phase (solvent) into gas phase, some of it returning to liquid phase. Under this condition, the ratio K=CL/CG is constant without relation to analyte concentration. This ratio is called distribution coefficient.

What is benzene exposure?

How are people exposed to benzene? People are exposed to benzene primarily by breathing air that contains the chemical. Workers in industries that produce or use benzene may be exposed to the highest levels of the chemical, although federal and state regulations have reduced these exposures in recent decades.

How do you get exposed to benzene?

What is benzene poisoning?

Benzene poisoning occurs when someone swallows, breathes in, or touches benzene. It is a member of a class of compounds known as hydrocarbons. Human exposure to hydrocarbons is a common problem. This article is for information only. DO NOT use it to treat or manage an actual poison exposure.

Is benzene toxic to inhale?

Acute (short-term) inhalation exposure of humans to benzene may cause drowsiness, dizziness, headaches, as well as eye, skin, and respiratory tract irritation, and, at high levels, unconsciousness.

What is the hazard of benzene?

Hazard Summary. Benzene is found in the air from emissions from burning coal and oil, gasoline service stations, and motor vehicle exhaust. Acute (short-term) inhalation exposure of humans to benzene may cause drowsiness, dizziness, headaches, as well as eye, skin, and respiratory tract irritation, and, at high levels, unconsciousness.

What is the reference concentration for benzene?

(4) EPA has established a Reference Concentration (RfC) of 0.03 milligrams per cubic meter (0.03 mg/m3) for benzene based on hematological effects in humans. The RfC is an inhalation exposure concentration at or below which adverse health effects are not likely to occur.

What is the detection and recognition odor threshold for benzene?

The American Industrial Hygiene Association’s detection and recognition odor thresholds for benzene are 61 ppm and 97 ppm, respectively. )–A calculated concentration of a chemical in air to which exposure for a specific length of time is expected to cause death in 50% of a defined experimental animal population.

What is the vapor pressure of benzene in MHG?

The vapor pressure for benzene is 95.2 mm Hg at 25 °C, and it has a log octanol/water partition coefficient (logKow) of 2.13. (1) Conversion Factors (only for the gaseous form): To convert concentrations in air (at 25°C) from ppm to mg/m 3