The broad-spectrum herbicide glyphosate (common trade name “Roundup”) was first sold to farmers in 1974. Since the late 1970s, the volume of glyphosate-based herbicides (GBHs) applied has increased approximately 100-fold. Further increases in the volume applied are likely due to more and higher rates of application in response to the widespread emergence of glyphosate-resistant weeds and new, pre-harvest, dessicant use patterns. GBHs were developed to replace or reduce reliance on herbicides causing well-documented problems associated with drift and crop damage, slipping efficacy, and human health risks. Initial industry toxicity testing suggested that GBHs posed relatively low risks to non-target species, including mammals, leading regulatory authorities worldwide to set high acceptable exposure limits. To accommodate changes in GBH use patterns associated with genetically engineered, herbicide-tolerant crops, regulators have dramatically increased tolerance levels in maize, oilseed (soybeans and canola), and alfalfa crops and related livestock feeds. Animal and epidemiology studies published in the last decade, however, point to the need for a fresh look at glyphosate toxicity. Furthermore, the World Health Organization’s International Agency for Research on Cancer recently concluded that glyphosate is “probably carcinogenic to humans.” In response to changing GBH use patterns and advances in scientific understanding of their potential hazards, we have produced a Statement of Concern drawing on emerging science relevant to the safety of GBHs. Our Statement of Concern considers current published literature describing GBH uses, mechanisms of action, toxicity in laboratory animals, and epidemiological studies. It also examines the derivation of current human safety standards. We conclude that: (1) GBHs are the most heavily applied herbicide in the world and usage continues to rise; (2) Worldwide, GBHs often contaminate drinking water sources, precipitation, and air, especially in agricultural regions; (3) The half-life of glyphosate in water and soil is longer than previously recognized; (4) Glyphosate and its metabolites are widely present in the global soybean supply; (5) Human exposures to GBHs are rising; (6) Glyphosate is now authoritatively classified as a probable human carcinogen; (7) Regulatory estimates of tolerable daily intakes for glyphosate in the United States and European Union are based on outdated science. We offer a series of recommendations related to the need for new investments in epidemiological studies, biomonitoring, and toxicology studies that draw on the principles of endocrinology to determine whether the effects of GBHs are due to endocrine disrupting activities. We suggest that common commercial formulations of GBHs should be prioritized for inclusion in government-led toxicology testing programs such as the U.S. National Toxicology Program, as well as for biomonitoring as conducted by the U.S. Centers for Disease Control and Prevention.

Introduction 5α-reductase inhibitors (5α-RIs), finasteride and dutasteride, have been approved for treatment of lower urinary tract symptoms, due to benign prostatic hyperplasia, with marked clinical efficacy. Finasteride is also approved for treatment of hair loss (androgenetic alopecia). Although the adverse side effects of these agents are thought to be minimal, the magnitude of adverse effects on sexual function, gynecomastia, depression, and quality of life remains ill-defined. Aim The goal of this review is to discuss 5α-RIs therapy, the potential persistent side effects, and the possible mechanisms responsible for these undesirable effects. Methods We examined data reported in various clinical studies from the available literature concerning the side effects of finasteride and dutasteride. Main Outcome Measures Data reported in the literature were reviewed and discussed. Results Prolonged adverse effects on sexual function such as erectile dysfunction and diminished libido are reported by a subset of men, raising the possibility of a causal relationship. Conclusions We suggest discussion with patients on the potential sexual side effects of 5α-RIs before commencing therapy. Alternative therapies may be considered in the discussion, especially when treating androgenetic alopecia.

A number of teacher workforce policies implicitly assume that job performance is a relatively stable attribute within teachers. We use longitudinal data on 5th grade teachers in North Carolina to assess this using value-added measures (VAMs) of job performance. We find that there is a permanent component of teacher performance that is stable in teachers over long periods-implying that workforce policies selecting teachers based on VAMs could effectively improve student achievement. But importantly, our time series model suggests that the permanent component of performance is considerably smaller than that which is often used to estimate workforce policy impacts.

SUMMARY (177±5dB re 1Pa p.-p.). The mean directivity indexes were 25dB for both species. The relatively low source levels in combination with the high directivity index may be an adaptation to reduce clutter when foraging in a coastal environment. We conclude that the small species-specific shifts in distribution of centroid frequencies around 130kHz may reflect character displacement in otherwise-stereotyped NBHF clicks.

Virtually all states require teachers to undergo licensure testing before participation in the public school labor market. This article analyzes the information these tests provide about teacher effectiveness. The authors find that licensure tests have different predicative validity for student achievement by teacher race. They also find that student achievement is impacted by the race/ethnicity match between teachers and their students, with Black students significantly benefitting from being matched with a Black teacher. As a consequence of these matching effects, the uniform application of licensure standards is likely to have differential impacts on the achievement of White and minority students.