Our Food: Packaging and Public Health

Humans have used packaging to store, protect, and transport all manner of foods for centuries. Over time packaging has evolved in response to public-health needs and marketing trends. Given that the average person encounters a variety of packaging materials throughout the course of a day, there is concern that exposures to certain constituents of these materials might pose some risks to human health. This article discusses some of the environmental health pros and cons of common packaging materials.

Which Fish Should I Eat?

The public receives advice about the consumption of fish from a variety of perspectives, including toxicologic, ecologic, nutritional, and economic viewpoints. As a result, consumers who want to know which fish to eat may encounter contradictory advice. Oken et al. reviewed published scientific literature, public health guidelines, and advisories related to fish consumption to identify areas of overlap and disagreement. The authors conclude that more comprehensive advice describing multiple impacts of fish consumption should be developed. They suggest developing a list of which fish to eat and which to minimize or avoid, taking into account the multiple perspectives and not solely the health effects of contaminants and nutrients, and they recommend that this list include links to more detailed resources that can be used by consumers who want more information. The authors urge governmental organizations to promote environmental remediation, eliminate sources of fish contamination, and establish policies that promote environmentally responsible and economically viable fishing practices.

Related News Article: Casting a Wider Net: The Quest for Better Guidance on Seafood Consumption

Health Impacts of Black Carbon and Methane Emission Controls

Tropospheric ozone and black carbon [BC; a component of fine particulate matter (PM_2.5)] are associated with premature mortality. Increasing levels of these environmental agents also have the capacity to alter global and regional climate. Anenberg et al. estimated the air quality and health benefits of reducing BC and methane, an ozone precursor, over the next 20–40 years following implementation of various emission control measures. The authors simulated the impacts of the mitigation measures on outdoor PM_2.5 and ozone concentrations using two composition-climate models, and they calculated associated changes in premature PM_2.5- and ozone-related deaths using epidemiologically derived concentration–response functions. For PM_2.5 and ozone, respectively, they estimated that fully implementing the mitigation measures could reduce global population-weighted average surface concentrations by 23–34% and 7–17% and avoid 0.6–4.4 and 0.04–0.52 million annual premature deaths globally in 2030; > 80% of the health benefits were estimated to occur in Asia. The authors estimated that implementation of all of the BC mitigation measures would be associated with most of the avoidable deaths. They conclude that methane and BC emission control measures, independent of carbon dioxide mitigation measures, would have substantial co-benefits for air quality and public health worldwide, potentially reversing trends of increasing air pollution concentrations and associated mortality in Africa and South, West, and Central Asia.

Related News Article: Global Bang for the Buck: Cutting Black Carbon and Methane Benefits Both Health and Climate

Malignant Epithelia Transform Normal Stem Cells

Cancer stem cells (CSCs) are likely critical to carcinogenesis and, like normal stem cells (NSCs), are affected by the microenvironment. Malignant cells release extracellular factors that modify tumor behavior. Inorganic arsenic, a human carcinogen, induces overproduction of CSCs in various model systems of carcinogenesis. Xu et al. examined whether the influence of arsenic-transformed malignant epithelial cells (MECs) is a possible factor in arsenic-associated CSC overabundance. They used transwell noncontact co-culture to study the effects of noncontiguous, arsenic-transformed prostate MECs on the WPE-stem isogenic human prostate NSC line. Cancer phenotype was assessed by secreted matrix metalloproteinases (MMPs), invasiveness, colony formation, and spheroid formation, and gene expression was assessed at protein and mRNA levels. NSCs co-cultured with MECs showed rapid hypersecretion of MMPs and marked suppression of the tumor suppressor gene PTEN. Co-culture with MECs also caused dysregulated self-renewal, differentiation-related gene expression patterns, and epithelial-to-mesenchymal transition in NSCs consistent with an acquired cancer phenotype. Interleukin-6, a cytokine involved in tumor microenvironment control, was hypersecreted by MECs. In NCSs, interleukin-6 exposure led to oncogenic alterations similar to those observed when NSCs were co-cultured with MECs. The authors suggest that arsenic-transformed MECs recruit nearby NSCs into a cancer phenotype, thereby potentially increasing CSC number. This may be a factor in arsenic-induced CSC overabundance observed in multiple model systems.

Related News Article: Bad Neighbors: Arsenic-Induced Tumor Cells Convert Normal Stem Cells into a Cancerous Phenotype