Last year I wrote about the health risks of using high heat when grilling. New reports tell us that open flames from both gas and charcoal can induce polycyclic aromatic hydrocarbons (PAHs) in cooked meat, chicken or any muscle meat on a grill. It is our skin and lungs that absorbs the toxins from the fumes while grilling. Entering our lungs and damaging our body organs.

Part of this article is based on the current study published in the Journal of Environmental Health Science and Engineering, titled “The effects of gas versus charcoal open flames on the induction of polycyclic aromatic hydrocarbons in cooked meat: a systematic review and meta-analysis. June 2020.

Polycyclic aromatic hydrocarbons (PAHs) are a group of organic compounds composed of at least two aromatic rings. As persistent pollutants, PAHs are known by the International Agency for Research on Cancer (IARC) for their probable carcinogenicity and mutagenicity to humans. The International Union of Pure and Applied Chemistry (IUPAC) has identified more than 100 PAHs, 16 of which have been listed by JECFA (the Joint FAO/WHO Expert Committee on Food Additives) as genotoxic and carcinogenic compounds.

The consumption of grilled meat is increasingly popular worldwide at home, outdoor and in restaurants because of its unique taste. However, barbecuing and gas grilling aren’t the only ways that PAH’s can form, they can come from, pan-frying, fried bacon, fried fish and any source where heat is high.

Chicken cooked without the skin has been found to have twice the levels of mutagens as chicken cooked with the skin left on.

Another study found that children who live in a home with a gas stove have a 42 percent higher risk of asthma symptoms and a 24 percent increased risk of being diagnosed with asthma. Nitrogen dioxide has been identified as a contributor to respiratory, cardiovascular, and immune system dysfunction and deterioration. When using a gas stove or cooktop, always turn the ventilation hood on.

Concerning the popularity of both gas and charcoal heating in meat cooking, it seems necessary to compare them in the view of food safety. A literature review showed that there is some studies aiming to compare the PAH content of gas and charcoal-cooked meat by utilizing various methodologies, with reporting different results. To shed light on the issue, the current study aimed to conduct a systemic review and meta-analysis of experimental studies comparing the PAH content of cooked meat prepared on open flames of gas and charcoal.

The aroma from grilling meats on high heat can produce cancer-causing compounds known as polycyclic aromatic hydrocarbons (PAHs). In a report on the National Cancer Institute’s website explains that both heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs) are chemicals formed when muscle meat, including beef, fish, or poultry, is cooked using high-temperature methods such as pan frying or grilling directly over an open flame. In laboratory experiments, HCAs and PAHs have been found to be mutagenic. That means that they cause changes in DNA that may increase the risk of cancer.

HCAs and PAHs become capable of damaging DNA only after they are metabolized by specific enzymes in the body, a process called “bioactivation.” Studies have found that the activity of these enzymes, which can differ among people, may be relevant to the cancer risks associated with exposure to these compounds.

HCAs are formed when amino acids (the building blocks of proteins), sugars, and creatine or creatinine (substances found in muscle) react at high temperatures. PAHs are formed when fat and juices from meat grilled directly over a heated surface or open fire drips into the surface or fire, causing flames and smoke. The smoke contains PAHs when adhered to the surface of the meat. PAHs can also be formed during other food preparation processes, such as smoking of meats.

HCAs are not found in significant amounts in foods other than meat cooked at high temperatures. PAHs can be found in other smoked foods, as well as in cigarette smoke and car exhaust fumes.

A study from China suggest letting your skin come in to contact with PAHs when you grill food is even more harmful than just savoring the aroma. Though eating barbecued meats is the most common source of exposure, just standing near a grill and breathing PAH-contaminated air can be risky, previous studies have researched this thoroughly. The same type of cooking at restaurants produces the same chemical formations to occur. They aren’t exempt.

Clothes can help protect you from the smoke, but only for a short period, the researchers noted in a journal news release. Once fabrics become saturated with contaminated, smoke enters the skin through our pores and absorbs high PAH levels.

To reduce your exposure to these toxic compounds, the researchers recommend laundering clothes immediately after you are back home and away from the grill. Or as soon as possible.

For the latest study, published May 23 of last year, in Environment Science & Technology, a team led by Eddy Y. Zeng at Jinan University closely examined skin exposure to PAHs from barbecue fumes and particles.

The researchers divide volunteers into groups based on various levels of exposure to grilled foods and smoke.

Urine samples revealed the greatest PAH exposure came from eating grilled foods, but skin contact was in second place, followed by inhalation of barbecued fumes.

Numerous studies have used detailed questionnaires to examine participants’ mean consumption and cooking methods. Researchers found that high consumption of well-done, fried, or barbecued meats was associated with increased risk of colorectal, pancreatic and prostate cancer.

Even though no specific guidelines for HCA/PAH consumption exist, concerned individuals can reduce their exposure by using several cooking methods:

• Avoid direct exposure of meat to an open flame or a hot metal surface and avoiding prolonged cooking times (especially at high temperatures) can help reduce HCA and PAH formation.
• Using a microwave oven to cook meat prior to exposure to high temperatures can also substantially reduce HCA formation by reducing the time that meat must be in contact with high heat to finish cooking.
• Removing charred portions of meat and refraining from using gravy made from meat drippings can also reduce HCA and PAH exposure.