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The coronavirus (COVID-19) is a threat to public health and caused several social, environmental, and economic problems. During the lockdown in different countries, waste generation has been significantly increased due to the high consumption of packaged food and increase the order of food via online and takeaway. This paper aims to investigate the impact of COVID 19 lockdown on food consumption and the subsequent change in waste generation in Oman. A quantitative research methodology was applied for this study using an online survey during the COVID 19 lockdown. The survey collected information on demographic data, awareness and attitudes toward food purchase behaviour, household food expenditure, and waste generation. The results show that 57.6% of the respondents believed that their food purchasing during the lockdown was increased as compared to before the lockdown. The main reason for increasing the food purchasing was the change in consumers behaviour and cooking more in households during the lockdown. This increase led to the increase in waste generation. One of the main reasons for the increased waste generation during the lockdown was the fact that people have spent more time at home. It was found that food waste and plastic packages were the highest increase (72% and 55%, respectively). These two types of waste are followed by cans and glass bottles with an increase of 68%. Other types of waste such as medical waste, electrical and electronic waste, and paper waste have shown no significant change in waste generation during the lockdown. Overall, this study provides useful information to further promote household food waste prevention behaviour, outlasting the COVID-19 crisis. The results from this study can be used by waste management and municipal utilities on consumption behaviour during emergency situations.

The concentrations and comparisons of total and available metals Cd, Cr, Ni, Pb and the metalloid As were examined in two adjacent acid forest soils in Greece under oak and beech together with the dependency of their availability. It was found that the soil in the beech plot had higher concentrations of total elements with the exception of the litter layer (L) where most metals did not differ. It is probable that the parent material of the beech soil contained some metamorphic mafic material. The surface soils for both stands were moderately enriched with Pb, Cd and As, whereas for Cr and Ni the enrichment was minimal. The concentrations of available elements (extracted with DTPA) were higher in the beech soil. The availability of most metals was affected by the pH, the organic C, the ratio of C/N and the total concentration of the metals. Through a Principal Component Analysis (PCA) analysis, it was found that 63-75% of the concentrations variance of the available metals was explained. The percentages of available metals with regard to their total concentrations in soils were higher in the beech plot in the FH layer but in the mineral layers, they did not differ apart from Pb. The concentrations of the metals in the leaves of both species in three consecutive years did not differ with the exception of Cd, the concentration of which was higher in the beech leaves.

Recent studies have indicated that PAEs (phthalic acid esters) are significant environmental pollutants with carcinogenic, teratogenic, and mutagenic effects. Urban soils can act as both a source and sink for city contaminants. This paper takes Changji, Xinjiang in Northwest China as the study area and explores the pollution characteristics and health risks of PAEs in the urban soils of arid areas. The analysis results indicate average concentration occurrences of 13.77 mg/kg and ranges from 0.29 to 119.72 mg/kg in the study area. Dibutyl phthalate (DBP) and di-(2-ethylhexyl) phthalate (DEHP) were the predominant PAEs in the urban soil of Changji. The highest average PAEs concentration appeared in winter, followed by autumn and spring and the lowest in summer; the seasonal variation was significant. The climate characteristics of arid regions and seasonal variations of source emissions were the primary influencing factors. The theoretical values of the non-carcinogenic and carcinogenic risk of PAEs were relatively small, all within the acceptable range. Values of non-carcinogenic risk and carcinogenic risk to children were much higher than the risks to adults. Children were the vulnerable groups most at risk for harmful pollutants, and the safety of their living environment should be the focus of more attention.

Catechol is used as an antioxidant, fungicide, and polymerization inhibitors in a variety of industries such as petrochemical. Catechol must be removed from effluents before it enters to environment. This study aimed to investigate combined UV radiation and persulfate process in removal of catechol from aqueous solutions. All experiments were performed in a batch reactor. Data analysis were done with Design of Experiment (DoE) software. The effects of various variables such as pH, initial persulfate concentration, and initial Catechol concentration were investigated. The findings indicated with increases in persulfate concentration and decrease in catechol concentrations, the removal efficiency increased. Acidic pH and UV radiation were the leading factors in removal of catechol. The optimum pH, persulfate concentration, and catechol concentration were obtained 7, 0.04 M, and 100 mg l-1, respectively. More removes of catechol was achieved in optimum conditions within contact time of 60 min. The synergic effects of UV and persulfate radical were about 88%. Approximately 60% of catechol was mineralized within contact time of 60 min. Persulfate radicals resulting from UV/S2O82- were the main effective oxidants in removal and mineralization of catechol. Owing to high removal efficiency of persulfate compounds which are, also, abundant and inexpensive, these can be applied in removal of persistent organic pollutants from aqueous solutions.