BPA Coats Cash Register Receipts
BPA Coats Cash Register Receipts
Update: see report on green chemistry pioneer John Warner's new research on BPA in receipts here.
by Sonya Lunder, Senior Analyst; David Andrews, Senior Scientist; and Jane Houlihan, Senior VP for Research
The plastic component bisphenol A (BPA) has been in the headlines nonstop as scientists, health experts and consumers press for a federal ban on food packaging made with this synthetic estrogen, shown to leach readily into infant formula, beverages and canned food. But most Americans are probably unaware that they are regularly exposed to the same endocrine-disrupting chemical in cash register receipts.
Two-fifths of the paper receipts tested by a major laboratory commissioned by Environmental Working Group were on heat-activated paper that was between 0.8 to nearly 3 percent pure BPA by weight. Wipe tests conducted with a damp laboratory paper easily picked up a portion of the receipts' BPA coating, indicating that the chemical would likely stick to the skin of anyone who handled them. The receipts came from major retailers, grocery stores, convenience stores, gas stations, fast-food restaurants, post offices and automatic teller machines (ATMs).
Major retailers using BPA-containing receipts in at least some outlets included McDonald's, CVS, KFC, Whole Foods, Walmart, Safeway and the U.S. Postal Service. Receipts from some major chains, including Target, Starbucks and Bank of America ATMs, issued receipts that were BPA-free or contained only trace amounts.
Scientists have not determined how much of a receipt's BPA coating can transfer to the skin and from there into the body. Possibilities being explored include:
- Oral exposure -- BPA moves from receipts onto fingers and then onto food and into the mouth.
- Dermal exposure -- BPA from receipts is directly absorbed through the skin into the body.
A study published July 11 by Swiss scientists found that BPA transfers readily from receipts to skin and can penetrate the skin to such a depth that it cannot be washed off (Biedermann 2010). This raises the possibility that the chemical infiltrates the skin's lower layers to enter the bloodstream directly. BPA has also been shown to penetrate skin in laboratory studies (Kaddar 2008).
EWG collected 36 receipts and commissioned the University of Missouri Division of Biological Sciences laboratory to investigate their BPA content. This laboratory is considered one of the world's foremost research facilities in its capability to detect environmentally relevant BPA concentrations.
The Missouri scientists found that the total mass of BPA on a receipt is 250 to 1,000 times greater than the amount of BPA typically found in a can of food or a can of baby formula, or that which leaches from a BPA-based plastic baby bottle into its contents. These data should not be interpreted to suggest that policymakers shift their focus from BPA contamination of food, which is widespread, to receipts. BPA exposure from food sources is ubiquitous and should remain the first priority of U.S. policymakers. However, a significant portion of the public may also be exposed to BPA by handling receipts. Since many retailers do not use BPA-laden thermal paper, this particular route of exposure is easy to correct.
Biomonitoring surveys by the federal Centers for Disease Control and Prevention have found BPA in the bodies of 93 percent of Americans over age 6. EWG analysis of CDC data has found that people who reported working in retail industries had 30 percent more BPA in their bodies than the average U.S. adult, and 34 percent more BPA than other workers. (CDC 2004). As of May 2009, 1 in 17 working Americans -- 7 million people -- were employed as retail salespersons and cashiers, according to the Bureau of Labor Statistics.
EWG's biomonitoring study of minority newborns, published last December, found BPA in 9 of 10 samples, marking the first detections of the chemical in the cord blood of U.S. infants. EWG has published a Safe Baby Bottle and Formula Guide to help parents of infants avoid BPA and other harmful substances during this critical window of development.
In animal tests, scientists have produced evidence that BPA can induce abnormal reproductive system development, diminished intellectual capacity and behavioral abnormalities and can set the stage for other serious conditions, such as reproductive system cancer, obesity, diabetes, early puberty, resistance to chemotherapy, asthma and cardiovascular system disorders. It has caused epigenetic changes, meaning alterations in the way genes switch off and on and genetic changes that can be passed on to the next generations.
Frequent exposures to relatively large amounts of BPA in receipts are an obvious concern to every shopper, but even more so to the legions of people who staff cash registers and bag groceries at tens of thousands of retailers across the country. These workers handle BPA-loaded receipts hundreds of times a day, with as yet unknown consequences for their health (Biedermann et al 2010). According to the U.S. Department of Labor’s Bureau of Labor Statistics, as of May 2009, the two largest U.S. occupations were “retail salespersons” and “cashiers,” with more than 7 million Americans in those jobs.
Retail workers carry an average of 30 percent more BPA in their bodies than other adults, It is unclear how much BPA-coated receipts contribute to people's total exposure to the ubiquitous plastics chemical. What is certain, however, is that since many retail outlets already use BPA-free paper for their receipts, this is one source of contamination that could easily be eliminated completely.
Thermal paper is widely used for point-of-sale receipts, prescription labels, airline tickets and lottery tickets. Thermal printers use paper that is coated with a dye and developer (BPA or an alternative chemical). Heat from the thermal printing head triggers a reaction between the dye and developer, allowing the black print to appear.
In an effort to quantify how much BPA would transfer to a person’s hand, the laboratory performed wipe tests on four BPA-laden receipts. In all four cases, BPA transferred from the receipts to the wipes. An average of 2.4 percent of the receipts’ total BPA content wiped off, suggesting that a person who handled receipts would be exposed to some BPA in the thermal paper. There have been no published studies of BPA residues inside pockets, purses and wallets, on wet produce in grocery bags or on the hands of people after they crumpled and discarded a receipt.
Since 60 percent of the receipts EWG collected did not have significant levels of BPA, it is apparent that many retailers are using alternatives. The leading U.S. thermal paper maker, Wisconsin-based Appleton Papers Inc., no longer incorporates BPA in any of its thermal papers (Raloff 2009). Reacting to concerns about the toxicity of BPA, the Japan Paper Association began to halt the use of BPA in 1998, completing the phase-out by 2003 (AIST 2007). EWG's analysis of three receipts collected in Japan at KFC, McDonald's and Starbucks found only trace amounts of BPA. In addition, 11 of 13 U.S.-based retailers whose receipts EWG tested used non-BPA paper in at least one outlet.
The U.S. Environmental Protection Agency (EPA) has initiated a program to evaluate the safety and availability of alternatives to BPA in thermal paper (EPA 2010).
EWG urges retailers to use BPA-free paper and to consider paperless options such as emailed electronic receipts. These measures could greatly reduce the volume of BPA disseminated by the retail industry and save paper in the bargain. Retailers should make public the identity of any chemicals used in the alternative they select. Very little information is publicly available on the now-common BPA alternatives for thermal receipts.
Tips to reduce exposures to BPA in receipts
- Minimize receipt collection by declining receipts at gas pumps, ATMs and other machines when possible.
- Store receipts separately in an envelope in a wallet or purse.
- Never give a child a receipt to hold or play with.
- After handling a receipt, wash hands before preparing and eating food (a universally recommended practice even for those who have not handled receipts).
- Do not use alcohol-based hand cleaners after handling receipts. A recent study showed that these products can increase the skin's BPA absorption (Biedermann 2010).
- Take advantage of store services that email or archive paperless purchase records.
- Do not recycle receipts and other thermal paper. BPA residues from receipts will contaminate recycled paper.
- If you are unsure, check whether paper is thermally treated by rubbing it with a coin. Thermal paper discolors with the friction; conventional paper does not.
Methodology and Findings. EWG collected 36 receipts from retailers in seven states and the District of Columbia:
- Ten national retail and service chains, including Walmart, Chevron and McDonald's;
- Three government establishments - the U.S. Postal Service and the cafeterias in the U.S. House of Representatives and Senate; and
- One local supermarket in Colorado.
We contracted with the analytical laboratory at the University of Missouri-Columbia's Division of Biological Sciences to perform the analysis. The laboratory weighed, measured and photographed the receipts, dissolved them in an alcohol, then analyzed them for BPA using a sensitive, standard BPA test method (High-Performance Liquid Chromatography (HPLC) with CoulArray detection).
The laboratory detected substantial amounts of BPA on 16 of 36 receipts at an average amount of 1.9 percent by weight, and a range of 0.8 to 2.8 percent (Table 1).
Table 1. Test Results - BPA in store receipts
|Establishment where receipt was obtained||Location||Total mass of BPA on receipt (milligrams)||Size of receipt (square centimeters)||Mass of BPA relative to mass of receipt||Mass of BPA relative to surface area of receipt (micrograms of BPA per square centimeter)||Percent of BPA that rubbed off of receipt onto wet wipe|
|National Supermarkets||Safeway||Berkeley, CA||20.7||1,006||2.8%||35.9|
|Whole Foods||Superior, CO||10.8||902||1.8%||25.7||0.71%|
|Gas station||Chevron||Berkeley, CA||0.0084||456||0.002%||0.06||*|
|Banks||Bank of America||Berkeley, CA||ND||805||ND||ND|
|Local supermarket||Sunflower Farmers Market||Boulder, CO||0.145||994||0.017%||0.22|
|U.S. Postal Service||Boulder, CO||23.6||1,600||2.0%||16.4||2.21%|
|U.S. House of Representatives Cafeteria||Washington, DC||5.42||494||1.3%||32.8|
|U.S. Senate Cafeteria||Washington, DC||0.00||540||0.0%||0.00|
|Retailers in Japan|
|Kentucky Fried Chicken||Sendai, Japan||0.0014||570||0.0%||0.01|
Source: EWG compilation of BPA test results from the University of Missouri Division of Biological Sciences Laboratory, for receipts collected by EWG.
* Only trace BPA levels were detected on wipe samples of receipts not coated with BPA.
Safeway supermarket receipts had the highest levels by several measures. Safeway receipts had 3 of the top 6 highest overall BPA levels. A store in the District of Columbia had the greatest total estimated mass of BPA (41 milligrams). A Berkeley, CA Safeway had the highest concentration of BPA relative to the paper mass (2.8 percent of the receipt weight). Safeway was one of two retailers that had detectable BPA in all three store locations sampled.
The receipt for a McDonald's Happy Meal™ purchased in Clinton, Conn. on April 21, 2010 had an estimated 13 milligrams of BPA. That equals the amount of BPA in 126 cans of Chef Boyardee Overstuffed Beef Ravioli in Hearty Tomato & Meat Sauce, one of the products with the highest concentrations of BPA in EWG's 2007 tests of canned foods (EWG 2007).
Source: BPA test results from the University of Missouri Division of Biological Sciences Laboratory, for receipts collected by EWG.
* BPA at trace level or not detected.
EWG also collected receipts from stores and bank ATMs in three or four cities for each of the ten national retail and service chains sampled. Analysis of the laboratory tests found that of the 10 stores and bank ATMs:
- One, Safeway, issued BPA-containing receipts in all cities.
- Six issued a BPA-laden receipt in at least one, but not all, outlets - CVS, Walmart, KFC, Whole Foods, Chevron, and McDonald's - indicating that these retailers use BPA-free receipts at some outlets.
- Three provided receipts that were BPA-free or contained only trace amounts at all locations - Bank of America, Target and Starbucks.
EWG also collected receipts from post offices and government cafeterias. All receipts from the U.S. Postal Service contained BPA. A receipt from the U.S. House of Representatives cafeteria contained BPA, while a receipt from the U.S. Senate cafeteria did not.
The laboratory performed four wipe samples on four BPA-laden receipts - 0.7-to-3.8 percent of the BPA detected on the receipt easily wiped off onto a lightly moistened, BPA-free laboratory paper, with an average of 2.4 percent wiping off.
EWG also collected receipts from three retailers in Japan, at KFC, Starbucks and McDonald's outlets in the city of Sendai. None contained BPA above trace levels. In our U.S. samples, KFC and McDonald's issued BPA-containing receipts in at least one location.
Sources of Americans' exposures to BPA. BPA exposure is ubiquitous in the U.S. population. The CDC's National Biomonitoring Program found the chemical in the urine of 93 percent of Americans age six and older (Calafat 2008).
Researchers have considered BPA contamination of canned foods and beverages to be the primary sources of exposure in most populations, especially for infants and children.
In 2007, Environmental Working Group published a ground-breaking study documenting that BPA had leached from epoxy can linings into more than half the canned foods, beverages and canned liquid infant formula randomly purchased at supermarkets around the country. In the absence of any U.S. regulation on BPA contamination of food, EWG has published an online guide to baby-safe bottles and formula.
However, a recent study suggests that other sources may also be important (Stahlhut 2009). These researchers measured urinary levels of BPA in 1,469 adults after variable periods of fasting. They expected BPA levels in urine to fall rapidly in the absence of new food exposures, since the chemical is excreted very quickly from the body. Instead, BPA levels dropped only slowly, leading them to theorize that BPA from sources other than food may be significant, or, alternatively, that BPA may be stored in human fat and released slowly and constantly into the body.
EWG assessed CDC biomonitoring data from Americans tested between 2003 and 2004 to learn if retail workers carry higher amounts of BPA in their bodies than other adults. CDC provided employment information for 916 of 1,862 adults tested. EWG analysis found that the 195 people who reported working in retail industries had 28 percent more BPA in their bodies than the average U.S. adult, and 34 percent more BPA than other workers. EWG also found that four of the five occupations with the highest BPA measurements may come in contact with receipts, including those in retail department stores, communications, retail food stores, and eating and drinking establishments (Table 2).
Table 2. CDC biomonitoring studies indicate that retail workers are exposed to more BPA than other adults
|Population tested||Number of people tested||Geometric mean concentration of BPA (ug/L)|
|Male (age 18 and above)||801||2.7|
|Female (age 18 and above)||864||2.3|
|All adults (age 18 and above)||1,665||2.5|
Source. EWG analysis of CDC biomonitoring data from samples collected from 2003-2004 (CDC 2004).
* Retail workers include people designated in CDC employment groups 23-28 (CDC 2004).
EWG recommends that retailers switch to non-BPA receipt technologies immediately to help reduce their employees' BPA exposures.
AIST. 2007. Risk ASsessment Document Series No. 4: Bisphenol A. National Institute of Advanced Industrial Science and Technology (AIST), November 2007. AIST07-A00001-4.
Biedermann S, Tschudin P, Grob K. 2010. Transfer of bisphenol A from thermal printer paper to the skin. Anal Bioanal Chem. Published online: July 11, 2010.
Calafat AM, Ye X, Wong LY, Reidy JA, Needham LL. 2008. Exposure of the U.S. population to bisphenol A and 4-tertiary-octylphenol: 2003-2004. Environmental Health Perspectives 116(1): 39-44.
CDC 2004. National Health and Nutrition Examination Survey Data 2003-2004. US Department of Health and Human Services, Centers for Disease Control andPrevention: National Centre for Health Statistics (NCHS). Hyattsville, MD, http://www.cdc.gov/nchs/nhanes/nhanes2003-2004/nhanes03_04.htm
EWG. 2007. Bisphenol A: Toxic plastics chemical in canned foods. Environmental Working Group, March 2007. http://ewg.org/reports/bisphenola
EPA. 2010. BPA Alternatives in Thermal Paper Partnership. U.S. Environmental Protection Agency, Design for the Environment. Washington DC. http://www.epa.gov/dfe/pubs/projects/bpa/index.htm
Kaddar N, Harthé C, Déchaud H, Mappus E, Pugeat M. 2008. Cuteanous Penetration of Bisphenol A in Pig Skin. Journal of Toxicology and Environmental Health, Part A. 71(8):471-73.
LaKind JS, Naiman DQ. 2010. Daily intake of bisphenol A and potential sources of exposure: 2005-2006 National Health and Nutrition Examination Survey. Journal of Exposure Science and Environmental Epidemiology:1-8
Raloff J. 2009. Concern about BPA: Check your receipts. Science News. October 7, 2009. http://www.sciencenews.org/view/generic/id/48084/title/Science_%2B_the_Public__ Concerned_about_BPA_Check_your_receipts
Stahlhut RW, Welshons WV, Swan SH. 2009. Bisphenol A data in NHANES suggest longer that expected half-life, substantial nonfood exposure, or both. Environmental Health Perspectives 117(5): 784-89.
APPENDIX - LABORATORY METHODOLOGY AND QUALITY ASSURANCE / QUALITY CONTROL PROCEDURES
Laboratory Methodology - EWG staff collected receipts in seven U.S. states -- California, Colorado, Connecticut, Iowa, Maryland, Oregon and Virginia -- and the District of Columbia.
Samplers wore clean, powder-free nitrile gloves (Dynarex). They received the receipt from the cashier and held it gently between two fingers. Once away from the cashier, samplers rolled the receipts with minimal handling and placed them into clean polyurethane 50 mL tubes (Fischer Scientific). They noted the time, date, location, items purchased, temperature and humidity as well as the location where receipts were rolled and tubed. ATM and gas station receipts were collected directly from the machines in most cases.
EWG sent receipts to a laboratory at University of Missouri-Columbia, Division of Biological Sciences in Columbia, Mo. The laboratory weighed, measured and photographed the receipts, analyzed for BPA and screened for bisphenol B, bisphenol S and bisphenol F, using high-performance liquid chromatography (HPLC) with CoulArray detection. The standard curve in our assay ranges from 0.05 -4 nanograms per HPLC run. Four receipts that had values below and above the range of the standard curve are considered to be outside the limit of quantitation of the assay. These estimated values were different from five samples labeled as "non-detectable (ND)," in which there was no evidence of BPA.
Digestion analysis: Lengths of receipt weighing 200 mg each were cut and placed in a glass tube. No attempt was made to control for the amount of printing on the receipt. The receipts were incubated in methanol (15 ml, to cover the receipt) for 3 hours at room temperature, with occasional agitation. The methanol was then poured into clean glass tubes and diluted for analysis.
Migration analysis : EWG selected 9 of the collected receipts for migration analysis. For these, a piece of lab wipe (KimWipe) was lightly dampened with methanol and wiped in a zigzag fashion across the top (printed) surface of a 5 cm by 5 cm piece of receipt. This wipe was then soaked in methanol for 3 hours at room temperature, and the methanol then decanted and analyzed for BPA.
Quality assurance / Quality control procedures
The laboratory found no detectable BPA on sampling materials, including KimWipes, gloves and shipping tubes.
The laboratory assessed recoveries of BPA from paper by spiking a piece of filter paper approximately 8-by-8 centimeters with BPA and soaking it in methanol, as described for the sales receipts. This method only approximates BPA recovery from receipts since the paper and coating matrices are different.
The laboratory also analyzed samples with added BPA to determine whether the sample extract quenches or augments BPA measurements. Recoveries in positive controls averaged 92 percent. Sample data values presented in this study are not corrected for recovery.
The laboratory did not detect BPB, BPF and BPS in the receipts tested. Unidentified peaks were seen in some receipt samples that did not contain BPA. Some of these appeared to reflect high concentrations.