If the almonds you are eating are not organic , then the likely hood of exposure to propylene oxide is high.
Currently there are to regulations for testing for Propylen oxide residue on nuts coming out of california.
So what exactly is Propylene Oxide?
Here is information from our own government and the CDC
The Food and Drug Administration (FDA), along with a technical review panel comprised of almondscientific experts, are responsible for evaluating and approving the treatment processes thatdemonstrate effectiveness in achieving a reduction of possible contamination in almonds while not impacting their quality and sensory attributes. To date, FDA has approved as acceptable forms of pasteurization for almonds.
- Oil roasting,
- Dry roasting,
- Steam processing
- Propylene oxide (PPO) processes
- Organic almonds will be pasteurized using treatments, such as steam pasteurization, that meet the USDA Organic Program’s national standards.
- Other forms of pasteurization continue to be researched, evaluated and tested. ABC worked over several years with leading experts and weighed all perspectives and issues in developing this industry-wide pasteurization plan.
With regard to labeling, the FDA regulates package labeling guidelines for all foods. The FDA has determined that raw almonds, whether treated via the steam or PPO methods or untreated, may be labeled raw under FDA guidelines. The ABC does not have any consumer labeling authority over almonds or products made with almonds.
Individual manufacturers and retailers determine their own labeling practices based on FDA requirements.
Propylene oxide is reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in experimental animals.
Propylene oxide is used primarily as a chemical intermediate in the production of other compounds (HSDB 2009). In the United States in 1993, propylene oxide was used to produce the following compounds:
- Polyurethane polyols (58%),
- Propylene glycols (22%),
- Glycol ethers (5.5%),
- Di- and tri-propylene glycols (3.5%),
- Miscellaneous compounds (polyalkylene glycols, allyl alcohol, and isopropanolamines) (11%) (CMR 2001).
- Polyurethane polyols are used to make polyurethane foams,
- propylene glycols are used primarily to make unsaturated polyester resins for the textile and construction industries.
Propylene oxide is also used in the preparation of :
- Oil demulsifiers.
It is approved for use as a direct and indirect food additive.
- Propylene oxide has been used as a fumigant for soil and in chambers for the sterilization of packaged foods.
- It is used as an herbicide, microbicide, insecticide, fungicide, and miticide (HSDB 2009).
- It is also used as a reactive diluent in preparations for embedding tissues for transmission electron microscopy, in detergent manufacture, and as a component of brake fluids (IARC 1994, HSDB 2009).
- The routes of exposure to propylene oxide are inhalation, ingestion, and incidental dermal exposure.
- Consumers may be exposed through ingestion of propylene oxide residues in foods resulting from its use as an indirect food additive or by contact with consumer products containing propylene oxide.
- EPA has established tolerance limits for propylene oxide based on residues from fumigation of cocoa beans, nutmeats, herbs and spices, and some fruits (e.g., figs, prunes, and raisins) (EPA 2006).
- Consumer products with the highest concentrations of propylene oxide include automotive and paint products. One automotive product lists propylene oxide as an ingredient at a concentration of 0.1% to 0.5% (HPD 2009).
From The Centers for Disease Control
J. Donald Millar, M.D., D.T.P.H. (Lond.)
Assistant Surgeon General
Director, National Institute for
Occupational Safety and Health
Centers for Disease Control
- Propylene oxide induced DNA damage (single-strand breaks) in rat hepatocytes and chromosomal aberrations (chromatid gaps, chromosomal gaps, breaks, and fragments) in rat liver cells and human lymphocytes.
- Dunkelberg  administered 15 or 60 mg of propylene oxide (99% pure) per kg of body weight in salad oil by gavage to groups of 50 female Sprague-Dawley rats 2 times/week for 150 weeks.
- Treated animals developed hyperplasia, hyperkeratosis, or papillomas of the forestomach (incidence rates were 7/50 at the 15-mg/kg dose and 17/50 at the 60-mg/kg dose) [Dunkelberg 1982].
- Squamous-cell carcinomas of the forestomach developed in a dose-dependent manner in rats treated with propylene oxide (incidence rates were 0/50 for controls, 2/50 at the 15-mg/kg dose, and 19/50 at the 60-mg/kg dose).
- The first of these tumors was observed during the 79th week in the high-dose group.
- One additional animal in the 60-mg/kg group had an adenocarcinorna.
Several systems exist for classifying a substance as a carcinogen. Such classification systems have been developed by:
- NTP [NTP 1985], the International Agency for Research on Cancer (IARC) [IARC 1985], and
- OSHA, in its “Identification, Classification, and Regulation of Potential Occupational Carcinogens” [29 CFR* 1990.112], also known as “The OSHA Cancer Policy.” niosh considers the OSHA classification system the most appropriate for use in identifying occupational carcinogens.
- Exposure to Propylene oxide has been shown to produce cancer and benign tumors in both rats and mice. niosh therefore recommends that propylene oxide be considered a potential occupational carcinogen in conformance with the OSHA Cancer Policy.