key: cord-0016286-yubl2jqq authors: Street, Maria Elisabeth; Bernasconi, Sergio title: Microplastics, environment and child health date: 2021-03-25 journal: Ital J Pediatr DOI: 10.1186/s13052-021-01034-3 sha: 1adab2a3529b57fabe9fab959052930dfd87c9b2 doc_id: 16286 cord_uid: yubl2jqq nan Maria Elisabeth Street 1* and Sergio Bernasconi 2 The substantial increase in scientific studies [1] in recent years has clarified and evidenced that the use of plastic material, widely employed in daily life due to the advantages it offers with respect to other materials, can cause environmental damage. In particular, several studies have focused on microplastics (MPs), defined on the basis of a size smaller than 5 mm. MPs are subdivided into two groups [2] : primary MPs, used both industrially as plastic pellets and in personal care products (i.e. toothpastes, nail polishes, sun creams, scrubs, bath gels) [3] and secondary MPs, derived from the plastic waste dispersed into the environment which undergoes progressive degradation because of photo and thermooxidative processes and mechanical abrasion [4] . These latter derive mainly from industrial packaging and textile fibers released into the washing water from machinewashed clothing [2] . Overall, it is estimated that between 75,000 and 300,000 t of microplastics are released into the environment each year in the EU alone [5] . It must also be borne in mind that MPs can release complex mixtures of chemicals into the environment as many types of additives are used in the industrial production of plastics to provide specific features (for example flame retardants, UV stabilizers, heat stabilizers, and plasticizers) [6] . Moreover, due to their hydrophobic surface, MPs can adsorb and concentrate to a high degree hydrophobic organic contaminants (HOCs) such as polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides and polychlorinated biphenyls (PCBs) [7] . They also accumulate heavy metals such as cadmium, zinc, nickel, and lead [8] . Several studies have shown the presence of MPs in marine waters [9] , in terrestrial soil [10] , in the air [11] and in tap water [12] in highly populated areas as in regions far from inhabited centers [13] . In other words, MPs are so ubiquitous [14] that scientists have suggested that they will represent an index of the geological era we are experiencing that some geologists define as anthropocene [15] . In addition, various researches have recently shown that MPs can be introduced into the human body, and are found in human organs and tissues [16] . Most commonly MPs are introduced into the body orally, and have been detected in several foods. Most studies have focused on foods of marine origin including invertebrates, crustaceans, and fish [17, 18] but MPs have been found also in sea salt coming from different countries [19] , primarily fragments but also filaments and films. Moreover, polyethersulfone and polysulfone have been reported as common types of MPs detected in branded milk samples [20] and have been found in bottled water, honey, beer, plastic teabags and soft drinks in addition [21] [22] [23] as well as in fruit and vegetables (particularly in apples and carrots) [24] . Moreover, MPs have been identified in the feces of human volunteers [25] . Based on the consumption of foodstuff, bottled water and on inhalation it has been estimated that a person's yearly intake in the USA is within a range from 39000 to 121000 particles of MPs [26] . The second mode of introduction of the MPs into the body is through inhalation. Using a Breathing Thermal manikin, Vianello et al. [27] concluded that MPs represent a non-negligible fraction of indoor airborne particulate, which can be both inhaled and ingested. Finally, the possibility of skin absorption should be considered even if there is no definitive evidence to prove this. Further experiences/studies on this aspect would be useful and are warranted [28] . At this stage the logical and fundamental question is: "what are the real risks of disease for humans having ascertained the presence of MPs within the body?" Based on current knowledge this question remains unanswered. However, although currently we are unable to give an exact answer, one must take into consideration the wide range of results obtained from studies in vitro and in animals, including mammals, that have allowed to understand how ingested microplastics pass the intestinal barrier leading to the hypothesis of possible negative effects on human health. Some recent papers have reviewed in detail the most significant results of this research [29, 30] . As exhaustively summarized by Plata et al. [28] , the experimental data have shown that the toxic action occurs by causing: chronic inflammation, changes in the immune response, neurotoxic effects and/or serving as a vector for mycroorganisms and /or toxic chemicals. It should be mentioned also that these actions may require a bioaccumulation phase and do not present in a short frame-time. Moreover, a very unexplored field, that must be investigated, are possible changes induced by MPs on the human microbiota which today is considered of great importance for the effects it can have on various immunological and metabolic disorders [31, 32] . Therefore, today there is a need to develop research on the impact that MPs can have on human health, avoiding easy mass-media alarmism and setting up work based on shared methodologies [33, 34] that also take into account the total exposure (exposome) that an individual can have towards plastic substances in general and /or towards chemical substances contained in plastics but not only in these [35] . As pediatricians, however, we must emphasize that research must also take into account the peculiarities of the developmental age. Children and adolescents have different sensitivity to chemicals than adults and this varies in the different stages of life [36] [37] [38] . supporting the need for specific methodologies [39] . Particular attention must be given to fetal life. It has been shown for the first time [40] that MPs can pass the placenta barrier which we already know is permeable to various potentially toxic substances [41] . We know from studies on the Developmental Origins of Health and Disease hypothesis how epigenetic modifications during fetal life can induce disease in adulthood [42] [43] [44] . In conclusion, current knowledge on the possible short and long term consequences of exposure to MPs on the health of children and adults should prompt to deepen further the relationships between environment and health. It would be desirable for pediatric scientific societies to take greater responsibility towards environmental issues both at the research level and at the training level of pediatricians. Finally, it may be useful to remember that even at this time when the viral pandemic is rightly attracting the maximum attention a question to be asked is whether and how the spread of the virus could also be favored by environmental pollution [45, 46] . The necessary use of face-masks has also opened the issue of these being a source of microplastics [47, 48] . Bibliometric profile of global microplastics research from 2004 to 2019 Environmental occurrences, fate, and impacts of microplastics Characterisation, quantity and sorptive properties of microplastics extracted from cosmetics Combined effects of UV exposure duration and mechanical abrasion on microplastic fragmentation by polymer type Communication from the commission to the european parliament, the council,the european economic and socialcommittee and the committee of thr regions A European Strategy for Plastics in a Circular Economy Brussels Microplastics in seafood and the implications for human health Ingested microplastic as a two-way transporter for PBDEs in Talitrus saltator Plastic and human health: a micro issue? Marine microplastic debris: an emerging issue for food security, food safety and human health Microplastic in terrestrial ecosystems Mini-review of microplastics in the atmosphere and their risks to humans Occurrence and identification of microplastics in tap water from China White and wonderful? Microplastics prevail in snow from the Alps to the Arctic Accumulation and fragmentation of plastic debris in global environments The geological cycle of plastics and their use as a stratigraphic indicator of the Anthropocene A detailed review study on potential effects of microplastics and additives of concern on human health Trophic transfer of microplastics and mixed contaminants in the marine food web and implications for human health Anthropogenic debris in seafood: plastic debris and fibers from textiles in fish and bivalves sold for human consumption The presence of microplastics in commercial salts from different countries Branded milks -are they immune from microplastics contamination? Potent impact of plastic Nanomaterials and micromaterials on the food chain and human health First study of its kind on the microplastic contamination of soft drinks, cold tea and energy drinks-future research and environmental considerations Review of micro-and nanoplastic contamination in the food chain Micro-and nano-plastics in edible fruit and vegetables. The first diet risks assessment for the general population Detection of various microplastics in human stool: a prospective case series Human consumption of microplastics Simulating human exposure to indoor airborne microplastics using a breathing thermal manikin Environmental exposure to microplastics: an overview on possible human health effects Potential health impact of environmental micro-and nanoplastics pollution Health impacts of environmental contamination of micro-and nanoplastics: a review Microplastics and the gut microbiome: how chronically exposed species may suffer from gut dysbiosis Interaction between microplastics and microorganism as well as gut microbiota: a consideration on environmental animal and human health Adverse outcome pathways potentially related to hazard identification of microplastics based on toxicity mechanisms Toward a unified framework for investigating micro (nano) plastics in packaged beverages intended for human consumption A critical perspective on early communications concerning human health aspects of microplastics The special vulnerability of children Timescales of developmental toxicity impacting on research and needs for intervention ethylhexyl) phthalate metabolites in urine show age-related changes and associations with adiposity and parameters of insulin sensitivity in childhood Environmental mixtures and children's health: identifying appropriate statistical approaches Plasticenta: first evidence of microplastics in human placenta Endocrine-disrupting Chemicals in Human Fetal Growth Epigenetic responses and the developmental origins of health and disease Current knowledge on endocrine disrupting chemicals (EDCs) from animal biology to humans, from pregnancy to adulthood: highlights from a National Italian Meeting Plastics in the time of COVID-19 pandemic: protector or polluter? A review of current knowledge on pollution, cigarette smoking and covid-19 diffusion and their relationship with inflammation The COVID-19 pandemic face mask waste: a blooming threat to the marine environment Single-use surgical face masks, as a potential source of microplastics: do they act as pollutant carriers? Authors' contributions Both authors contributed equally to the conceptualization, research of the Literature and writing of this manuscript. The authors read and approved the final manuscript.