The effects of nonyl phenoxypolyethoxyl ethanol on cell damage pathway gene expression in SK-NSH cells

Health, Pesticide Adjuvants, and Inert Ingredients: California Case Study Illustrates Need for Data Access

BACKGROUND

Many pesticide products are mixtures of multiple chemicals. These include active ingredients intended to kill pests, and so-called inert ingredients intended to improve the physical characteristics of the product. In addition, shortly before applying a pesticide product, applicators often mix adjuvants into the sprayer tank. Adjuvants are products designed to improve the performance or physical properties of a pesticide spray mixture. Manufacturers may use a particular chemical compound both as an inert ingredient within pesticide products and as a component of adjuvant products. Nonetheless, regulations dictate that data on use are publicly available only for the portion used in adjuvants. Adjuvants are exempt from federal registration, but are defined as pesticides in California. Based on that definition, California has identified α-(p-nonylphenyl)-ω-hydroxypoly(oxyethylene) (APNOHO) as the most widely used pesticide in the state, applied to more than 10 million acres annually. That quantified use includes only agricultural acres treated with adjuvants containing APNOHO. Total APNOHO use is likely higher because manufacturers also use the chemical as an inert ingredient within pesticide products, although data on such use are shielded by regulation.

OBJECTIVES

We use APNOHO as a case study to demonstrate that the use of adjuvants and inert ingredients is difficult to track because relevant information is not publicly available. We synthesize information that suggests widespread agricultural use of alkylphenol ethoxylates, such as APNOHO, may pose significant human and environmental health risks. We then make recommendations for future research and policy.

METHODS

We used information from California's pesticide use reporting system and the U.S. Environmental Protection Agency (EPA) to estimate use of APNOHO. We used U.S. EPA and European databases, as well as published research, to identify human and environmental health hazards of APNOHO. We focused on research showing that APNOHO is an endocrine-disrupting chemical.

DISCUSSION

Within California, APNOHO is applied in more than 150 adjuvant products. Nationwide, it is used as an inert ingredient in at least 650 pesticide products. Exposure to APNOHO is associated with endocrine disruption, birth defects, and aquatic toxicity. We suggest that the case of APNOHO illustrates the larger problem of a lack of publicly available data on use and toxicity of many adjuvants and pesticide inert ingredients. We recommend that researchers and regulators include adjuvants and inert ingredients when evaluating pesticide hazards, including endocrine disruption. We also recommend regulatory requirements to identify all ingredients on product labels. https://doi.org/10.1289/EHP10634.

Clinical characteristics of stress cardiomyopathy in patients with acute poisoning

Patients who attempt intentional suicide suffer from physical or emotional stress. This situation might be an important factor that causes takotsubo cardiomyopathy. We retrospectively investigated the clinical features of Takotsubo cardiomyopathy in patients with acute poisoning. This study included patients who were admitted from January 2010 to December 2015 because of intentional poisoning by ingestion. Among these patients, we selectively collected data of patients who underwent an echocardiogram. We divided the patients into three groups according to the echocardiogram; the non-cardiomyopathy group, the global hypokinesia group, and the takotsubo cardiomyopathy group. One hundred forty-seven patients were analyzed in this study. One hundred thirty-one patients had normal cardiac function without regional wall motion abnormality. Global hypokinesia was observed in five patients. The overall incidence of takotsubo cardiomyopathy was 7.5% (11/147). Levels of cardiac enzymes including CK-MB, Troponin T, a marker of cardiac muscle ischemia, were higher in the global hypokinesia group and the takotsubo cardiomyopathy group compared with the non-cardiomyopathy group. The most commonly consumed poison was organophosphate in the takotsubo cardiomyopathy group. In conclusion, takotsubo cardiomyopathy may be one of the cardiac complications in patients who attempt suicide by consuming a poison.

Human cholestatic hepatitis owing to polyoxyethylene nonylphenol ingestion: A case report

RATIONALE

The purpose of this study was to identify the chemical responsible for cholestatic hepatitis in a 55-year-old woman who ingested 1,1'-iminodi (octamethylene) diguanidinium triacetate (iminoctadine triacetate), a fungicide. The fungicide formulation was also composed of polyoxyethylene nonylphenol (NP-40) and methanol.

PATIENT CONCERNS

Severe cholestatic hepatitis developed, which led to the patient's death on day 88 of hospitalization. Post-mortem necropsy of the liver showed focal hepatocyte necrosis involving mostly the mid-zone, along with intracytoplasmic and intracanalicular cholestasis.

DIAGNOSES

To identify the chemical responsible for hepatic injury, the cellular toxicity of all chemicals in the fungicide formulation was assessed in HepG2 cells using the 3-(4,5-dimethylthiaxol-2yl)-2, 5-diphenyl tetrazolium bromide test.

OUTCOMES

Viability of cells treated with the surfactant NP-40 was significantly lower (P < .001), but that of cells treated with other components of the fungicide, including the active ingredient, iminoctadine triacetate, was unaffected. Fluorescence-activated cell sorting analysis confirmed that necrosis was induced in HepG2 cells treated with 25-80 μM of NP-40, while significant numbers of apoptotic cells were not detected.

LESSONS

NP-40 appears to be the chemical responsible for the patient's irreversible hepatic injury, accompanied by intracytoplasmic and intracanalicular cholestasis.