The question of whether the small paper receipts handed out at stores pose a health risk has become a common public concern. This worry stems from the realization that the paper is coated with a chemical mixture that reacts to heat, allowing text to appear without traditional ink. This specialized material, known as thermal paper, relies on these chemical components to function, and their potential to interact with the human body drives the current health discussion.
Identifying the Chemicals in Thermal Paper
The specialized coating on thermal paper contains a colorless dye and a chemical developer that react when heated. The most recognized developer used for decades is Bisphenol A (BPA), which produces the dark image on the receipt. Due to health concerns, many manufacturers have replaced BPA with a similar compound, Bisphenol S (BPS), and market their products as “BPA-free.” These bisphenol compounds are not chemically bound to the paper fibers; they exist as a fine, powdery layer mixed into the coating. This unbound nature allows the chemicals to be easily dislodged and transferred upon contact.
How Chemicals Transfer to the Body
The primary route of human exposure from thermal receipts is dermal absorption, where chemicals transfer directly to the skin upon handling. Brief contact with a receipt can transfer microgram quantities of the bisphenol to the fingers. Once on the skin, the chemical is absorbed into the bloodstream, a process that can occur rapidly.
The rate of chemical absorption increases significantly when the skin’s natural barrier function is reduced. Using alcohol-based hand sanitizers, applying hand lotions, or having moist or oily hands can enhance the amount of bisphenol absorbed. Additionally, the chemical residue can be transferred from the hands to other surfaces, including food or the mouth, presenting a secondary route of exposure.
Assessing the Health Risk
The question of whether receipts cause cancer requires understanding how these chemicals act within the body. Both BPA and BPS are classified as endocrine-disrupting chemicals (EDCs) because they interfere with the hormonal system. They can mimic the natural hormone estrogen, binding to receptors and potentially altering normal biological functions. This estrogen-mimicking activity is the basis for health concerns, as hormone balance is necessary for development, metabolism, and reproductive health.
While high-level, long-term exposure to EDCs is linked to adverse outcomes like reproductive problems and metabolic disorders, direct evidence linking typical, brief receipt handling to cancer remains low or inconclusive by major regulatory bodies. Research suggests that the dermal absorption route, which bypasses the liver’s initial detoxification process, may result in higher levels of the active chemical circulating compared to ingestion.
The primary concern focuses on individuals with chronic, high-frequency exposure, such as retail cashiers who handle receipts for hours each day. Preclinical studies have shown that BPS, the common replacement for BPA, may contribute to the growth of certain hormone-sensitive cancer cells, such as breast and prostate cancer. Regulatory actions, such as California’s Proposition 65, now require consumer warnings for BPS exposure due to its classification as a reproductive toxicant.
Simple Steps to Reduce Exposure
The most effective way to reduce exposure to these chemicals is to decline a paper receipt and opt for a digital version whenever possible. If a paper receipt is necessary, handle it as briefly as possible and immediately place it into a wallet or bag, preferably with the printed side folded inward.
To further minimize exposure, avoid touching thermal paper after applying hand sanitizer, lotion, or any oily substances, as these products increase absorption. The most practical mitigation step is to wash hands thoroughly with soap and water immediately after handling any receipt, especially before eating or preparing food. For workers who handle rolls of thermal paper frequently, wearing protective gloves is a simple measure to minimize daily exposure.