How water companies might protect themselves from (some) pollution incident responsibility
Published on: 15 Aug 2023
By: Andy Godley
Personal care products (PCPs) are consumer products that are applied externally to the body. These include body wash, shampoo, conditioner, deodorant, toothpaste, moisturiser, skin care, lip balm, and hand soap. A 2004 survey by the Environmental Working Group found that over 25% of women, and one in 100 men, use at least 15 personal care products (PCPs) daily [1]. Within these PCPs are 12,000 chemicals, of which only 20% are recognised as safe for humans and the environment. Of the plethora of chemicals of concern used in all PCPs, 12 in particular stand out, these are the so-called ‘Dirty Dozen’ and include parabens, parfum/fragrance, and triclosan.
Removal of PCPs at Wastewater Treatment Plants
Wastewater treatment plants have varying efficacy when it comes to removing PCPs, ranging between 40% to 100% removal efficiency. When removed from wastewater, PCPs accumulate in sewage sludge, which is often spread on land as fertiliser. When PCPs aren’t removed from wastewater, they enter surface and marine waters through effluent.
Not so Fragrant Fragrance
Fragrance and parfum are particularly prevalent and were found to be present in 56% of 12,500 PCPs surveyed in Canada by the David Suzuki Foundation [2]. There are around 3,000 chemicals that are used in fragrances, the composition of which doesn’t have to be disclosed in the manufacturing process. Environment Canada has categorized several synthetic musks as persistent, bioaccumulative and/or toxic, and they have been detected in fish and aquatic sediment.
Reef Safe or Reef Damaging Sunscreen?
UV filters found in sunscreens can enter the environment via wastewater, or directly from recreational activities. Wastewater has been shown to be a significant method of transfer of UV filters into the environment. You may have heard the term ‘reef safe’ in reference to UV filters; these are UV filters that purport to be safe to coral reefs. They are commonly called ‘mineral sunscreens’, and contain inorganic UV filters that act to physically block, absorb or scatter UV radiation. The inorganic compounds approved by European Regulation for sunscreen are titanium dioxide (TiO2) and zinc oxide (ZnO). Despite inorganic UV filters being touted as ‘reef safe’, studies have shown toxic effects on algae and aquatic organisms [3,4,5,6,7,8]. The toxicity of ZnO and nano-ZnO in particular are well documented in several marine organisms. Toxicity has been associated with the release of Zn++ ions and oxidative stress due to reactive oxygen species (ROS) generation (the formation of highly reactive chemicals), which can damage cells and DNA. Consensus is mixed with respect to TiO2 toxicity, with some papers reporting negligible effects on aquatic organisms. Despite this, a dramatic increase in toxicity is observed when TiO2 is exposed to strong sunlight or UV radiation, as it stimulates the generation of reactive oxygen species.
Organic UV filters are synthetic chemicals which act to absorb UV radiation. They are popular with consumers as they produce a lightweight, easily absorbed sunscreen. However, they have been found in several aquatic organisms at high concentrations and have been shown to bioaccumulate within muscles and lipids. Bioaccumulation through the food chain has also been observed. Some Organic UV filters have been found to cause coral bleaching at low concentrations, with one study estimating that 10% of reefs are likely to bleach due to UV filter pollution [9]. Furthermore, some studies have shown that some organic UV filters possess endocrine disruption capacities, with effects on the reproduction of aquatic organisms reported [10,11].
Disrupting Parabens
Parabens are preservatives that possess antimicrobial properties. Their widespread use means they are prevalent in high concentrations in raw wastewater, with one study finding them in concentrations of up to 30,000 ng/L [12]. The removal of parabens from wastewater is effective (>90%), however their widespread use in PCPs means they are ubiquitous in the water environment and have recently been detected in bottled drinking water. Parabens have been found to display endocrine disrupting activity in animals and aquatic organisms.
Protect or Damage
Triclosan is an antimicrobial preservative used in personal care products, such as hand soaps, shampoos, detergents, toothpastes, sunscreen, and deodorants. It is one of the top10 most commonly detected organic compounds in wastewater due to its widespread use in PCPs and the extensive use of these products. It was found at concentrations of 2140–5260 ng/L in the Parisian sewage network. This was scaled up to a national mass load of 18.8–22.2 tons/year. During wastewater treatment, triclosan can be converted into chlorinated derivatives which are more toxic and more persistent. Triclosan is ubiquitous in the water environment and found in both water and sediments, and has been found to bioaccumulate in a variety of aquatic and terrestrial organisms.
The Future: Education and Control
Source control is a key mechanism in effectively reducing PCP release into the environment. Introducing more stringent regulation, such as the 2018 English and Scottish ban on products containing microbeads, is likely the most effective route. Similarly, education is key.
Raising education can influence buying habits and allow consumers to make informed choices that align with their environmental beliefs.
The Environmental Working Group has a database that reviews and rates personal care products and the risks they pose to the environment.
References:
[1] Environmental Working Group (2012) Cosmetic and Your Health – Why This Matters. Available from: https://isthmuswellness.com/wp-content/uploads/2012/10/Cosmetic-and-Your-Health-Why-This-Matters.pdf
[2] David Suzuki Foundation (2010) What’s inside? That counts. Available from: https://davidsuzuki.org/wp-content/uploads/2017/10/REPORT-whats-inside-counts-survey-toxic-ingredients-cosmetics.pdf
[3] Menard et al. (2011) Ecotoxicity of nanosized TiO2. Review of in vivo data. Environmental Pollution, Volume 159, pp. 677-684. Available from: http://www.bionanoteam.com/wp-content/uploads/Menard%202011%20ENVPOL.pdf
[4] Xiong et al. (2011) Effects of nano-scale TiO2, ZnO and their bulk counterparts on zebrafish: Acute toxicity, oxidative stress and oxidative damage. Science of the Total Environment, Volume 409, pp. 1444-1452. Available from: https://citeseerx.ist.psu.edu/document?repid=rep1&type=pdf&doi=c934282db99cd00f8297b992ced5536889f151af
[5] Hund-Rinke & Simon (2006) Ecotoxic Effect of Photocatalytic Active Nanoparticles (TiO2) on Algae and Daphnids. Environmental Science and Pollution Research. Available from: https://www.researchgate.net/profile/Kerstin-Hund-Rinke/publication/6877660_Ecotoxic_Effect_of_Photocatalytic_Active_Nanoparticles_TiO2_on_Algae_and_Daphnids/links/59837ac0458515b420c963f4/Ecotoxic-Effect-of-Photocatalytic-Active-Nanoparticles-TiO2-on-Algae-and-Daphnids.pdf
[6] Clemente et al. (2014) Toxicity assessment of TiO2 nanoparticles in zebrafish embryos under different exposure conditions. Aquatic Toxicity, Volume 147, pp. 129-139. Available from: https://www.sciencedirect.com/science/article/abs/pii/S0166445X13003743
[7] Kahru & Dubourguier (2010) From ecotoxicology to nanoecotoxicology. Toxicology, Volume 269, Issues 2-3, pp. 105-119. Available from: https://www.sciencedirect.com/science/article/abs/pii/S0300483X09004442
[8] Zhang et al. (2016) Toxic effects of nano-ZnO on marine microalgae Skeletonema costatum: Attention to the accumulation of intracellular Zn. Aquatic Toxicology, Volume 178, pp. 158-164. Available from: https://www.sciencedirect.com/science/article/abs/pii/S0166445X1630217X
[9] Danovaro et al. (2008) Sunscreens Cause Coral Bleaching by Promoting Viral Infections. Environmental Health Perspectives, Volume 116, No. 4. Available from: https://ehp.niehs.nih.gov/doi/full/10.1289/ehp.10966
[10] Kunz et al. (2006) Comparison of In Vitro and In Vivo Estrogenic Activity of UV Filters in Fish. Toxicological Sciences, Volume 90, Issue 2, pp. 349-361. Available from: https://academic.oup.com/toxsci/article/90/2/349/1658390
[11] Kim & Choi (2014) Occurrences, toxicities, and ecological risks of benzophenone-3, a common component of organic sunscreen products: A mini-review. Environmental International, Volume 70, pp. 143-157. Available from: https://www.sciencedirect.com/science/article/abs/pii/S0160412014001585
[12] Haman et al. (2015) Occurrence, fate and behavior of parabens in aquatic environments: A review. Water Research, Volume 68, pp. 1-11. Available from: https://www.sciencedirect.com/science/article/abs/pii/S0043135414006605