CAS RN: 121-75-5

Disposal Methods

SRP: Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in air, soil or water; effects on animal, aquatic and plant life; and conformance with environmental and public health regulations. If it is possible or reasonable use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination.
SRP: Wastewater from contaminant suppression, cleaning of protective clothing/equipment, or contaminated sites should be contained and evaluated for subject chemical or decomposition product concentrations. Concentrations shall be lower than applicable environmental discharge or disposal criteria. Alternatively, pretreatment and/or discharge to a permitted wastewater treatment facility is acceptable only after review by the governing authority and assurance that "pass through" violations will not occur. Due consideration shall be given to remediation worker exposure (inhalation, dermal and ingestion) as well as fate during treatment, transfer and disposal. If it is not practicable to manage the chemical in this fashion, it must be evaluated in accordance with EPA 40 CFR Part 261, specifically Subpart B, in order to determine the appropriate local, state and federal requirements for disposal.
Product: Offer surplus and non-recyclable solutions to a licensed disposal company; Contaminated packaging: Dispose of as unused product.
Malathion may be disposed of by absorbing in vermiculite, dry sand, earth, or a similar material ... & /disposing of so as to meet local, state, & federal regulations/.
Incineration together with flammable solvent in furnace equipped with afterburner and scrubber is recommended.
The following wastewater treatment technologies have been investigated for Malathion: Biological treatment and reverse osmosis.
Malathion is reported to be "hydrolyzed almost instantly" at pH 12; 50% hydrolysis at pH 9 requires 12 hr. Alkaline hydrolysis under controlled conditions (0.5 N NAOH in ethanol) /0.5 N sodium hydroxide in alcohol/ gives quantitative yields of (CH30)2P(S)SNA, whereas hydrolysis in acidic media yields (CH30)2P(S)OH. On prolonged contact with iron or iron-containing material, it is reported to break down and completely lose insecticidal activity. Incineration together with a flammable solvent in a furnace equipped with afterburner and scrubber is recommended. Recommendable methods: Incineration & landfill. Peer review: Only small amt may be landfilled. (Peer-review conclusions of an IRPTC expert consultation (May 1985))
Molten salt combustion: The melts contained either sodium carbonate or potassium carbonate. The use of potassium carbonate is of interest because the combustion product, potassium chloride can be used as a fertilizer. Destruction of the pesticide was greater than 99.9%. No pesticides were detected in the melt; however, traces of pesticides were detected in the off-gas. The conc of pesticides in the off-gas were generally well below the TLV.
Safe Disposal of Pesticides. The best way to dispose of small amounts of excess pesticides is to use them - apply them - according to the directions on the label. If you cannot use them, ask your neighbors whether they have a similar pest control problem and can use them. If all of the remaining pesticide cannot be properly used, check with your local solid waste management authority, environmental agency, or health department to find out whether your community has a household hazardous waste collection program or a similar program for getting rid of unwanted, leftover pesticides. These authorities can also inform you of any local requirements for pesticide waste disposal. /Residential users/
Safe Disposal of Pesticides. An empty pesticide container can be as hazardous as a full one because of residues left inside. Never reuse such a container. When empty, a pesticide container should be rinsed carefully three times and the rinsewater thoroughly drained back onto the sprayer or the container previously used to mix the pesticide. Use the rinsewater as a pesticide, following label directions. Replace the cap or closure securely. Dispose of the container according to label instructions. Do not puncture or burn a pressurized container like an aerosol - it could explode. Many communities have programs to recycle household waste such as empty bottles and cans. Do not recycle any pesticide containers, however, unless the recycling program specifically accepts pesticide containers and you follow the program's instructions for preparing the empty containers for collection. /Residential users/
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