Beyond the outdoors: indoor air quality guidelines and standards - challenges, inequalities, and the path forward.

In the last few decades, indoor air quality (IAQ) has become a major threat to public health. It is the fifth leading cause of premature death globally. It has been estimated that people spend ∼90 % of their time in an indoor environment. Consequently, IAQ has significant health effects. Although IAQ-related standards and guidelines, policies, and monitoring plans have been developed in a few countries, there remain several global inequalities and challenges. This review paper aims to comprehensively synthesize the current status of widely accepted IAQ guidelines and standards. It analyzes their global implementation and effectiveness to offer insights into challenges and disparities in IAQ policies and practices. However, the complexity of domestic environments and the diversity of international standards impede effective implementation. This manuscript evaluates international, national, and regional IAQ guidelines, emphasizing similarities and differences. In addition, it highlights knowledge gaps and challenges, urging the international scientific community, policymakers, and stakeholders to collaborate to advance IAQ standards and guidelines. The analysis evaluates the efficacy of guidelines, identifies deficiencies, and offers recommendations for the future of domestic air quality standards.

Thymus vulgaris (thyme) inhibits proliferation, adhesion, migration, and invasion of human colorectal cancer cells.

Colorectal cancer (CRC) remains one of the most common malignancies and a leading cause of cancer-related deaths. Its prognosis remains poor for patients with several grades of this disease. This underscores the need for alternative modalities, such as herbal medicines, to treat this disease. A commonly used plant that appears to be of high medicinal value is Thymus vulgaris L. However, the effects of this plant on the malignant behavior of human CRC cells remains poorly investigated. This study was undertaken to determine the anticancer efficacy of T. vulgaris extract (TVE) in CRC cells. Our results show that TVE inhibits proliferation in a concentration- and time-dependent fashion. This decreased proliferation was concomitant with increased apoptotic cell death as evidenced by increased caspase3/7 activity. Moreover, TVE also decreased adhesion to fibronectin in a concentration-dependent manner. The migratory and invasive capacities of HCT116 cells were significantly inhibited by TVE. Taken together, these data suggest that the TVE inhibits malignant phenotype of colon cancer cells. Therefore, T. vulgaris could have an anticancer effect and that some of its bioactive compounds may prove to be effective treatment modalities for human CRC.