In this study, we measured the occurrence of organophosphate esters (OPEs) and phthalates in the settled dust (floor and air conditioner filter dust) and in suspended particulate matter (PM10) from different microenvironments (households (n = 20), offices (n = 10) and hotels (n = 10)) of Jeddah, Saudi Arabia. Bis (2-Ethylhexyl) phthalate (DEHP) was the major pollutant (contributing >85% of total chemicals burden) in all types of indoor dust with a concentration up to 3,901,500 ng g⁻¹. While dibutyl phthalate (DBP) and DEHP together contributed >70% in PM10 (1900 ng m⁻³), which indicate PM10 as a significant source of exposure for DBP and DEHP in different Saudi indoor settings. Tris (1-chloro-2-propyl) phosphate (TCPP) was the major OPE in PM10 with a concentration of up to 185 ng m⁻³ and the occurrence of OPEs in indoor dust varied in studied indoor settings. The estimated daily intake (EDI) of studied chemicals via dust ingestion and inhalation of PM10 was below the reference dose (RfD) of individual chemicals. However, estimated incremental lifetime cancer risk (ILCR) with moderate risk (1.5 × 10⁻⁵) for Saudi adults and calculated hazardous index (HI) of >1 for Saudi children from DEHP showed a cause of concern to the local public health.

Besides the lack of studies regarding applying elevated CO₂ (eCO₂) as a strategy to improve the chemical composition of anise (Pimpinella anisum L.) seeds, studies on its interaction with seed developmental stages and origin are very limited. The seed yield, chemical composition, and biological activity of 6 aniseed accessions (Egypt, Tunisia, Syria, Turkey, Yemen, and Morocco) were investigated during three developmental stages (immature, premature, and mature) under control and elevated CO₂ conditions. Mature seeds from all aniseed accessions had significantly higher (p < 0.05) dry weight (DW) percentages than premature and immature seeds. The highest DW percentages were recorded in Egypt and Morocco accessions. Seed maturation increased nutrients and antioxidant metabolites in most eCO₂-treated accessions. In contrast, essential oils were decreased by seed maturation, while eCO₂ reversed this effect. Essential oil-related precursors (e.g., phenylalanine) and enzyme activities (3-Deoxy-d-arabino-heptulosonate-7-phosphate synthase (DAHPS) and O–methyltransferase) decreased with seed maturity. However, high CO₂ reduced this impact and further induced the other essential oil-related precursors (shikimic and cinnamic acids). Consequently, eCO₂ provoked changes in the antioxidant and hypocholesterolemic activities of aniseeds, particularly at mature stages. Overall, eCO₂ application, as an efficient way to improve aniseed growth, essential oil metabolism, and chemical composition, was affected by seed maturation and origin. Future studies of eCO₂-treated aniseeds as a nutraceutical and pharmaceutical product are suggested.

People may spend a significant amount of their daily time in cars and thus be exposed to chemicals present in car dust. Various chemicals are emitted from during car use, contaminating the car dust. In this study, we compiled published and unpublished data on the occurrence of phthalates, flame retardants (FRs), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs) in Saudi car dust. Phthalates, a class of chemical commonly used as plasticizers in different car parts, were the major pollutants found in car dust, with a median value of ∑phthalates 1,279,000 ng/g. Among other chemicals, organophosphate flame retardants (OPFRs) were found to be between 1500–90,500 ng/g, which indicates their use as alternative FRs in the car industry. The daily exposure to Saudi drivers (regular and taxi drivers) was below the respective reference dose (RfD) values of the individual chemicals. However, the estimated incremental lifetime cancer risk (ILCR) values due to chronic exposure to these chemicals was >1 × 10⁻⁵ for taxi drivers for phthalates and PAHs, indicating that the long-term exposure to these chemicals is a cause of concern for drivers who spend considerable time in cars. The study has some limitations, due to the small number of samples, lack of updated RfD values, and missing cancer slope factors for many studied chemicals. Despite these limitations, this study indicates the possible range of exposure to drivers from chemicals in car dust and warrants further extensive studies to confirm these patterns.

High raw material prices and rivalry from the food industry have hampered the adoption of renewable resource-based goods. It has necessitated the investigation of cost-cutting strategies such as locating low-cost raw material supplies and adopting cleaner manufacturing processes. Exploiting waste streams as substitute resources for the operations is one low-cost option. The present study evaluates the environmental burden of biopolymer (polyhydroxyalkanoate) production from slaughtering residues. The sustainability of the PHA production process will be assessed utilising the Emergy Accounting methodology. The effect of changing energy resources from business as usual (i.e., electricity mix from the grid and heat provision utilising natural gas) to different renewable energy resources is also evaluated. The emergy intensity for PHA production (seJ/g) shows a minor improvement ranging from 1.5% to 2% by changing only the electricity provision resources. This impact reaches up to 17% when electricity and heat provision resources are replaced with biomass resources. Similarly, the emergy intensity for PHA production using electricity EU27 mix, coal, hydropower, wind power, and biomass is about 5% to 7% lower than the emergy intensity of polyethylene high density (PE-HD). In comparison, its value is up to 21% lower for electricity and heat provision from biomass.

Teachers in technology education shops (TESs) in high schools are at risk from exposure to occupational hazards, including physical work demands and chemicals, particulate matter and noise, as well as non-optimal working conditions negatively affected by temperature, humidity, and lighting. This study evaluated the exposure to noise of 17 TES teachers working in 17 wood-working, metal-working, and automotive shops in selected high schools in British Columbia, Canada, and examined the quality of the acoustical teaching environments due to background noise. This study characterized noise control measures in the sampled TESs and observed the safety practices of teachers during TES classes. The results of this investigation indicated that almost 60% of the participating teachers were exposed to unacceptable levels of noise during teaching and working in TESs. It also showed that TES acoustical environmental quality was adversely affected by high background noise levels due to poor room designs and settings. Practical recommendations were provided to reduce and control the exposure to noise in TESs and to enhance the quality of health, safety, and quality of teaching environment in these TESs.

Data on arsenic (As) and other potentially toxic elements (PTEs) in Pakistani retail meats are limited, constraining evidence-based dietary risk assessment and management. This study aimed to determine the concentrations and profiles of As and seven other PTEs (Cr, Ni, Mn, Pb, Cd, Cu, Zn) in commonly consumed meats and to evaluate the associated non-carcinogenic health risks. Ninety-two paired liver and muscle samples from broiler chicken, goat (mutton), and beef cattle were collected from four cities across the Indus Plain and analyzed using inductively coupled plasma mass spectrometry (ICP-MS). Dietary exposure was evaluated using estimated daily intake (EDI), target hazard quotient (THQ), and hazardous index (HI) under typical and high-consumption scenarios. Overall, Zn and Cu exhibited the highest concentrations, followed by Mn and Cr, whereas As, Pb, Ni, and Cd occurred at comparatively lower but environmentally relevant levels. Beef liver exhibited the highest contamination levels, exceeding FAO/WHO permissible limits for Pb, Cu, and Cd in up to 40% of samples. In contrast, mutton and beef muscle contained the highest As and Zn concentrations, while chicken muscle showed elevated Cr levels. Multivariate statistical analysis revealed three dominant co-variation patterns, suggesting potential contamination pathways: (i) geogenic groundwater sources enriched with As, Cr, and Ni; (ii) atmospheric and industrial dust inputs linked with Pb, Cd, and Mn; (iii) mineral-enriched feed additives potentially contributing to elevated Zn and Cu, particularly in poultry. Under high-consumption scenarios, THQ values for As, Cr, Cu, and Zn exceeded the safety threshold (THQ > 1), highlighting beef products as the dominant source of chronic dietary risk. Overall, the findings highlight pronounced tissue- and species-specific accumulation trends, and emphasizes the urgent need for stricter feed and water quality control measures to minimize dietary exposure to PTEs.