This research based on PC data aimed at verifying whether during COVID-19 pandemic lockdown there were variations of exposure frequencies to specific product categories possibly associated to the containment measures and to the recommendations disclosed by the health authorities.
Italy has been the first Western country to adopt the most restrictive lockdown measures in the first months of 2020. Since PPC provides consultancies for the whole national territory, covering about 40% of those referring to all ten Italian PCs , the results obtained are representative of the entire Italian situation.
This is the first study using all EuPCS third-level categories and some of their sub-categories. Among all EuPCS categories, the attention was specifically focused on those involved in disinfecting and cleaning activities.
Considering the biological characteristics, the observed number of male patients slightly decreased during the lockdown period (March–May 2020) in comparison with the expected value. This finding may be attributed to women taking greater responsibilities to manage the disinfection of different settings, particularly the domestic ones. On the other hand, exposures in workplaces decreased in a highly significant way. This evidence is in line with the reduction of occupational injuries during COVID-19 lockdown reported by the National Institute for Insurance against Accidents at Work (INAIL) . Soave et al.  showed a 200% increase of occupational exposures during January–May 2020 but the small population involved does not allow making a comparison with the present study.
Among age groups, the class 1–5 years shows a not statistically significant increase during the lockdown period. Children’s exposures to disinfectants are a matter of great concern for Li et al.  (2020), who highlight that, due to their more frequent mouthing activities, children have consistent higher exposures to disinfectants than other age classes. The percentage difference calculated for the age class 11–19 years shows a highly statistically significant reduction of exposures during the lockdown. In fact, it seems that young people have significantly changed their lifestyle habits in this period, spending more time at home and mainly preferring sedentary activities . These unhealthy behaviours might have avoided other physical activities involving accidental exposures to dangerous chemicals. On the other hand, the reduction of physical activities may have led to a decrease in mental wellbeing .
While normally PPC mainly receives hospital calls (about 82% of consultancies come from emergency departments), a highly significant decrease was observed during the lockdown period. On the other hand, the number of non-hospital calls significantly increased, particularly because of calls from private citizens. This evidence could highlight a tendency of the population not to access hospitals or general practitioners if not strictly necessary, a fact in line with the recommendations given during COVID-19 pandemic. Other Italian [5, 23] and European  PCs also reported this trend.
The ocular route of exposure shows an increased percentage in comparison with the expected frequency, reaching the statistical significance with children aged 1–5 years. A statistically significant increase of paediatric ocular exposures to alcohol-based hand sanitizers (ABHS) from April to August 2020 are reported by Martin et al. , though considering subjects younger than 18 years.
In March–May 2020 symptomatic cases decreased in a lowly significant way, but among those with a Moderate PSS the statistical significance is high. This finding is mainly driven by a decrease of occupational exposures; in fact, high severities are significantly linked to this kind of exposures (p = .0002) (data not shown). Also Le Roux et al.  detected a significant decrease of exposures at work (− 45.5%; p < .001) in March–April 2020 in comparison with the same period of the previous 2 years, and at the same time they observed a decrease in severity (moderate/severe − 17.2%). On the contrary, data from US PCs, where containment measures were less restrictive in that period, did not report the same decrease .
Moreover, fewer intentional exposures and the increased percentage of 1–5 years’ children’s exposures may have also contributed to a lower severity of the clinical picture: in many cases the effectiveness of children’s exposures is uncertain so most of them have little clinical relevance.
To categorize the products included in this study, the EuPCS developed by ECHA was used . The advantage of this tool is that the intended use is easier to assign in comparison with other categorizations based on chemical structures. Nevertheless, ambiguous categorizations are still possible. Another limitation, in considering the purpose of a PC, is that this categorization system covers only product categories needing CLP classification, excluding other potentially toxic agents like cosmetics, animals, plants, food, drugs, tobacco (only E-liquid for E-cig is mentioned in the EuPCS). A certain advantage is that some product categories driven by specific regulations (Regulation (EU) No 528/2012 for Biocidal products, Regulation (EC) No 1107/2009 for Plant protection products ) maintain their original categorization in the EuPCS.
In this research, EuPCS allowed the categorization of products not only for consumer use, but also for professional and industrial use.
Among Cleaning, care and maintenance products (PC-CLN), Bleaching products for cleaning or laundry use (PC-CLN-3) and Drain cleaning products (PC-CLN-5) are the subcategories of most interest. Regarding the first, a 4.3% increase in exposures during the lockdown period was detected and the difference becomes highly statistically significant with male subjects belonging to the adult class 20–65 years. Since this evidence cannot be observed neither among female subjects nor among other age classes, it could be related to mistakes in handling these products made by non-professional and non-skilled/habitual users. Other authors commented the increase in household product exposures observed in many developed countries arguing that the probable reason for the high incidence detected could be ascribed to careless storage, ignorance, non-compliance with prescribed instructions for use and negligible parental supervision in case of children . In the European Union a survey highlighted that the 70% of European citizens use the label to obtain information about the potential danger of a chemical, although chemical hazard pictograms are usually not very understood . A more recent U.S. survey verified an important knowledge gap in the safe use of cleaners and disinfectants among the adult population . Inadvertent exposures indicated that the general public/non-professionals pay little or no attention to the instructions for use of cleaners and disinfectant products. Also Chang et al. , in evaluating data from American PCs, found that, among cleaner categories, bleaches accounted for the largest percentage of the increase (n. 1949; 62.1%). Increased exposures to bleaches seem to be temporally subsequent to advises reported in all the main Italian mass media including guidelines issued to prevent COVID-19 circulation, recommending to disinfect surfaces with chlorine and alcohol based products. Fortunately, bleach intoxication from inhalation or ingestion of small amounts due to accidental reasons is not normally of clinical significance . This evidence may further explain the low percentage of moderate/severe cases registered in March–May 2020. Considering the subgroup of Drain cleaning products (PC-CLN-5), a significant decrease in comparison with the expected value was observed. Moreover, among gender and age classes, the statistically significant difference becomes greater with male subjects of the adult class 20–65 years. Since these products are often referred to work contexts, this finding proves to be in line with the decrease of occupational exposures.
Among Detergents and auxiliaries for laundry and dishwashing (excludes biocidal products) (PC-DET), two different trends could be observed: on the one hand, there was a highly statistically significant decrease of Laundry detergents (PC-DET-1) probably caused by LLDC exposures of children aged 1–5 years; on the other, a significant increase in exposures of the same age class was detected for Dishwashing detergents (PC-DET-3). Differently, during COVID-19 crisis, Gulamhusein and Sabri  saw an increase in ocular exposures to LLDC among Canadian children. When investigating American NDPS data among children aged < 6 years, Gaw et al.  saw a declined trend by 55.5% from 2015 to 2017.
A possible explanation to the opposite tendencies observed could be as follows: with regard to Laundry detergents, the confinement reduced the possibility to go out and so the frequent need to wash clothes. On the other side, confinement doubtlessly led to an increase in the number of meals consumed at home, with a consequent increase in dishwashing activities. This high percentage in the age class 1–5 years underlines the need of a greater parental supervision when using products not suitable for children.
Regarding Biocidal products, a statistically significant increase during the lockdown period was observed. This result is probably due to Disinfectants. Chang et al.  observed a similar trend, although the statistical significance was not evaluated. Increased calls regarding household disinfectants were registered by several PCs around the world [5, 8, 9, 32]. In the present study, the statistical significance was specifically reached for Disinfectants and algaecides not intended for direct application to humans or animals, while Biocidal products for human hygiene (PP-BIO-1) only show a not statistically significant increased percentage. In the recent past, Wieck et al.  performed a study to investigate the knowledge about the appropriate use of biocidal products through a standardised questionnaire fed to German consumers. The research highlighted how only the 21% of consumers provided the exact definition of biocide. Nevertheless, the majority of the interviewees seemed not to be aware when and where they were actually using specific biocidal products. As a matter of fact, the product types mentioned in the interview often did not correspond to those the researchers actually found in interviewees’ houses. The highest percentage of the interviewees failed to mention disinfectants used for surfaces (17%). This type of biocides (PP-BIO-2) are often perceived as simply cleaners with a lower risk associated compared, for example, to Insecticides (PP-BIO-18). A survey of the Joint Research Centre of the European Commission  highlighted that more than a half of EU citizens always read the instructions before using pesticides and insecticides, but the reliance on the instructions is less common for other categories of chemical products. This underestimation of the risk could have led to dangerous exposures especially regarding disinfectants for surfaces frequently used in COVID-19 period.
Considering Cosmetics, both Handwashing soaps and Handwashing gel products show a statistically significant increase in March–May 2020 with respect to the expected value. In both cases, children aged 1–5 years mainly drive this increase. This evidence is consistent with the findings of Hakimi and Armstrong , who pointed out a significant increase in daily calls to US PCs regarding paediatric hand sanitizer exposures in March 2020 compared to March 2018–2019 and to January–February 2020, yet referring to children aged 12 years and younger.
Limitation to the study
As mentioned before, ambiguous categorizations using the EuPCS are possible. Furthermore, the trade name of the products is sometimes not completely reported so it was not easy to identify the right EuPCS third-level category. For certain products, the statistical significance highlighted an association between the increasing frequency of exposures and the lockdown period, but the magnitude of the effect (Cohen’s w index) is generally small.