Cell Phones Could Be a Source of Flame Retardant Exposure

Levels of organophosphate esters (OPEs) — compounds widely used as flame retardants and plasticizers to increase durability — found on cell phones and other handheld devices could be significantly associated with the amount of OPE metabolites in the urine, warn Canadian researchers.

OPEs have been linked to adverse health outcomes, such as reduced cognitive abilities in children and papillary thyroid cancer in adults, as well as worse in vitro fertilization outcomes.

Congqiao Yang, PhD, Department of Earth Sciences, University of Toronto, Ontario, Canada, and colleagues looked at OPE exposure through air and dust on home and electronic devices in more than 50 women.

The research, which was published online December 4 in Environment International, revealed that the women were exposed to several OPEs, with a significant correlation between the compounds found on their hands and the presence of metabolites in the urine.

In a press release, senior author Miriam L. Diamond, PhD, also of the University of Toronto, said: “What we don’t know for certain though is whether electronic devices are the source of the chemicals or an indicator of total exposure from other sources, or both.”

She continued, “Earlier this year the US Consumer Product Safety Commission granted a petition to ban the use of certain harmful flame retardant chemicals in electronics and other products.”

“The OPEs identified in this new study are often used as replacements for the banned chemicals, and increasing evidence indicates that these replacement chemicals are harmful as well.”

Children Especially Vulnerable: Wash Devices and Hands

The new findings come amidst calls for increased focus on the environmental and human health impacts of electronics. Existing electronics industry standards cover thermal, electrical, optical, and even acoustic product safety, but do not specify how materials should be screened for possible toxicological impacts.

Diamond told Medscape Medical News that exposure to chemicals such as those tracked in this study is of particular concern among children. She explained this is not only because of cumulative lifetime exposure, “but it’s also because kids are more vulnerable.”

“They’re vulnerable because their organ systems are still developing, so we want to be particularly cautious about kids’ exposures to toxic chemicals.”

In any case, she recommends that all phone and handheld device users be conscious about the amount of time they spend using their devices and to clean them from time to time. “Washing your hands is a good idea,” she said, “and washing your phone periodically is a good idea.”

“Very few people actually wash their phones,” Diamond pointed out, adding: “Your phone picks up the signal of all the things that your hands have been touching plus what’s in the phone itself.”

Diamond added that, for their next study, she and her colleagues would “like to look at children’s exposure through electronic devices, particularly because kids are given electronic devices at younger and younger ages.”

She continued, “You have really small kids being looked after by a cell phone now rather than by a human, so you wonder what the implications are.”

“Kids have a lot of hand to mouth contact, kids are always putting their hands in their mouths, so we’re very keen to look at what happens with little kids and electronic devices.”

Are Cellphones the Chicken or the Egg of OPE Exposure?

To investigate the sources of exposure to OPEs, Yang and her team recruited 51 participants in a population-based, case-control study of women with and without breast cancer.

The median age of the women was 41 years, and 78% had breast cancer. The women were predominantly white, highly educated homeowners, with 54% reporting an average household income of over $100,000.

The women completed a questionnaire about home characteristics, including thermal insulation type; personal demographic and lifestyle data, including use of personal care products and hand washing frequency; and presence and usage of major electronic devices and upholstered furniture.

The team also performed two in-home assessments, separated by approximately 3 weeks, to record particle levels in respirable air and floor dust in bedrooms (n = 51) and the most commonly used rooms (n = 26).

The palms and backs of hands of participants were wiped. Surface wipes of electronic products that operated at elevated temperatures or were in frequent contact with hands were also taken.

Forty-four participants also provided urine samples an average of 2 months before the first home visit. Overall, 23 OPEs were analyzed in the air, dust, and wipe samples, and eight OPE metabolites were assessed in the urine samples.

Six of the 23 OPEs tested were detected in over 80% of air samples, and seven had detection frequencies over 70% in dust samples, with no significant differences between the bedroom and most-used room.

Palms had higher concentrations of OPEs than the backs of the hands.

For all nine OPEs detected on electronic devices, concentrations on handheld devices (for example, cell phones, home phones, and tablets) were significantly higher than those seen for non-handheld devices, such as TVs (P ≤ .001).

Statistical analysis using hand wipes, cell phone wipes, and dust explained 8% of 33% of the variation in creatinine-adjusted urinary metabolites; air concentration did not have explanatory power.

The team writes, “Our results showed that exposure of some OPEs in these women can be explained by levels found on their cell phones.”

“The results do not allow us to distinguish between whether the cell phone is acting as a source of OPEs or rather a time- and space-integrated indicator of OPE exposure; likely both explanations are reasonable.”

They add, “Cell phone wipes could provide an integrated indicator of exposure to flame retardants and plasticizers accumulated from multiple microenvironments, particularly since most people are in frequent contact with their cell phones that are infrequently washed.”

Circulating BRAF may aid in papillary thyroid cancer diagnosis, follow-up.

The evaluation of circulating BRAF V600E has the potential for use in the diagnosis and follow-up of patients with papillary thyroid carcinoma, according to researchers in Italy.

To determine whether the BRAF V600Emutated allele in cell-free DNA has a role in the diagnosis and follow-up of papillary thyroid carcinoma, researchers detected the allele and quantified it by an allele-specific real-time quantitative polymerase chain reaction assay in plasma from 103 patients affected by nodular goiter. Forty-nine healthy patients and 16 patients with non-nodular thyroid diseases were included as controls for the study.

The percentage of circulating BRAF V600Ewas significantly different between patients and controls and throughout different cytological categories of ultrasound-assisted fine needle aspiration(FNA). Specifically, percentages were higher among patients with follicular lesions (18.7%; P<.001) and those considered suspicious of malignancy (27.1%; P=.001) vs. controls.

Further, patients with a histopathological diagnosis of papillary thyroid carcinoma displayed a greater percentage of circulating BRAF V600E(P=.035) vs. those with benign histology, according to data.

Blood was drawn from 19 patients 3 to 6 months after surgery and after radioactive iodine treatment when necessary. Among these, circulating percentages of BRAF V600E were significantly lower than in presurgical samples (P<.001).

Using the receiver operating characteristic curve analysis, researchers also reported that the diagnostic performance of circulating BRAF V600E resulted in an area under the curve of 0.797, with maximum specificity of 65% and sensitivity of 80%. They assessed the predictive value of BRAF V600E in patients with follicular lesions; the positive predictive value was 33% and the negative predictive value was 80%.

“The use of BRAF V600E as a circulating marker could have several important clinical applications. In the diagnostic setting, it would integrate the data obtained from cytological analysis of FNA, providing more complete information in particular cases such as multinodular goiters where it is not possible to sample all nodules by FNA,” researchers wrote. “The availability of circulating markers could play an important role also in the short- and long-term follow-up of patients with previous thyroid cancer.”

Further research is warranted before this can be implemented in clinical settings, they wrote.

Source: Endocrine Today