Author Archives: ToxStrategies

In accordance with their Endocrine Disruption Screening Program (EDSP), the US Environmental Protection Agency (EPA) recently released the Tier 1 screening data for various pesticide chemicals. In these Tier 1 assays, 52 pesticide chemicals were tested to determine their potential to interact with hormone pathways. Of the 52 chemicals evaluated, there was no evidence for potential interaction with any of the endocrine pathways tested for 20 chemicals. Fourteen chemicals showed potential interaction with one or more pathways, but EPA already has enough information to conclude that they do not pose a risk. Of the remaining 18 chemicals, all 18 showed potential interaction with the thyroid pathway, 17 of them with the androgen pathway, and 14 with the estrogen pathway. The EPA will decide which of these pesticides will move on to Tier 2 testing.

ToxStrategies’ own Dr. Susan Borghoff assisted in the EDSP, having implemented more than 40 studies associated with the Tier 1 screening visit this site right here. As an expert in endocrine disruption, Dr. Borghoff is often cited for her organization of a 2013 workshop, Lessons Learned, Challenges, and Opportunities: The US Endocrine Disruptor Screening Program, detailing the information and progress made in the EDSP. Dr. Borghoff organized and chaired a symposium at the 2013 American College of Toxicology Meeting entitled Endocrine Disruption Screening – Status of the US EPA and EU Programs: State of the Science and Slate for the Future in which she presented a talk entitled The US EPA Endocrine Disruptor Screening Program (EDSP) Tier 1 Assays: Retrospective Performance Evaluation.

Dr. Borghoff is well versed in evaluating chemical-specific data from  EPA’s EDSP21 ToxCast database, which contains the results of the estrogen and androgen specific in vitro assays. She also has experience developing and preparing  “Other Scientifically Relevant Information” (OSRI) documents to determine if specific Tier I assays can be waived, and/or providing an approach to evaluate the weight of evidence for Tier 2 testing.

For more information on the EDSP Tier 1 Assessments, please click here.

On July 23, the US House of Representatives passed bill H.R. 1599, the Safe and Accurate Food Labeling Act of 2015 that would preempt state laws regulating the labeling of genetically modified organisms (GMOs) in foods.  The vote was 275- 150. Representative, Mike Pompeo (R-KS) and G.K. Butterfield (D-NC), introduced the bill with the goal of creating a uniform, national system to govern the premarket review and labeling of genetically engineered foods (foods from or containing GMOs).

Key objectives of the Safe and Accurate Food Labeling Act of 2015 are to:

• Require the Food and Drug Administration (FDA) to conduct a safety review of all new plant varieties used for genetically engineered food before those foods could be introduced into commerce.
• Uphold FDA’s authority to specify special labeling if necessary to protect health and safety.
• Create a legal framework, subject to FDA oversight, regulating the use of label claims regarding the use or absence of genetically engineered food or food ingredients.
• Direct FDA to develop a Federal definition for “natural” claims on product labels
• Allow foods to be labeled as GMO-free, if desired, by participation in a USDA-accredited certification process (Similar to the USDA Organic Standard

ToxStrategies staff will continue monitor the progress of the Safe and Accurate Labeling Act of 2015 as it is of great importance to the food and animal food industries xenical over the counter.

You can learn more about the Safe and Accurate Food Labeling Act of 2015 and track the status of the bill here. You can find out more about the Food and Consumer Products Practice at ToxStrategies by visiting here.

The US National Oceanic and Atmospheric Administration’s (NOAA) Office of Response and Restoration recently made its Chemical Aquatic Fate and Effects (CAFE) database software available to the public. This software can be used to estimate the aquatic fate and effects for thousands of different chemicals, oils, and dispersants. The program can be downloaded and run on either Mac or Windows platforms. CAFE has two modules: (1) the Aquatic Fate module, that can be used to predict how a particular chemical will behave in the environment using data such as chemical properties; and (2) the Aquatic Effects (toxicity) module, which estimates the compound’s potential toxicity to various species (e.g., fish, crustaceans, mollusks, coral).

A copy of the free software can be downloaded here.

On July 2, 2015, the Center for Environmental Health (CEH) submitted a petition to the Office of Health Hazard Assessment (OEHHA) for an administrative rulemaking to repeal or amend the Maximum Allowable Dose Level (MADL) for lead under Proposition 65.  The basis for the petition was three-fold: (1) the original MADL for lead, established in 1989, did not meet the standards set forth for determining a MADL under Proposition 65, (2) OEHHA did not re-evaluated the MADL for lead in 2013 when it changed the basis for listing lead as a reproductive toxicant under Proposition 65, and (3) an appeals court ruling (Envt’l Law Found. V. Beech-Nut Nutrition Corp. [2015] 235 Cal.App.4th 307) had the effect of increasing the MADL from 0.5 ug/day to 7 ug/day.  In response to this petition, OEHHA will initiate a rule making to update the existing MADL for lead.  Given that lead has been the subject of numerous lawsuits and/or 60-day notices under Proposition 65, a change in the MADL for lead could have significant implications for companies doing business in California.

ToxStrategies scientists have substantial experience assisting our clients with Proposition 65 compliance, including derivation of safe harbor levels and estimating exposure to listed chemicals.  We will follow OEHHA’s rulemaking process closely and provide future updates as warranted.

Documents pertaining to CEH’s petition and OEHHA’s response can be found here.

ToxStrategies is pleased to announce a new publication titled Duodenal crypt health following exposure to Cr(VI): Micronucleus scoring, γ-H2AX immunostaining, and synchrotron X-ray fluorescence microscopy. ToxStrategies’ own Dr. Chad Thompson is the lead author on this publication, while several other ToxStrategies’ scientists also served as co-authors.

This research provides a comprehensive assessment of micronuclei in the crypts of Swiss roll duodenal sections from B6C3F1 mice following Cr(VI) exposure.  The study results found:

• Oral gavage of 50 mg/kg cyclophosphamide significantly increased micronuclei.
• Cr(VI) in drinking water (up to 180 ppm) for 7 days did not increase micronuclei.
• Chromium was localized to duodenal villi by X-ray fluorescence microscopy.
• γ-H2AX immunostaining did not differ between vehicle-and Cr(VI)-treated mice.

This paper was published in Mutation Research and is available in the August 2015 issue. A free copy of the complete paper can be downloaded here.

The US Environmental Protection Agency (EPA) just released a draft database of 1,173 hydraulic fracturing-related chemicals that were listed in the external review draft Assessment of the Potential Impacts of Hydraulic Fracturing for Oil and Gas on Drinking Water Resources (released June 4, 2015). The database provides physicochemical and toxicological information from a host of different sources, including: EPI Suite, LeadScope, QikiProp, Reaxys, IRIS, PPRTV, ATSDR, among others. The database also contains background information about how the list of chemicals was compiled.

The full draft database can be downloaded here.

On June 11, 2015, the US Environmental Protection Agency (EPA) released two technical guidance documents for evaluating vapor intrusion:

• OSWER Technical Guide for Assessing and Mitigating the Vapor Intrusion Pathway from Subsurface Vapor Sources to Indoor Air (VI Guidance)
• Technical Guide for Addressing Petroleum Vapor Intrusion at Leaking Underground Storage Tank Sites (Petroleum UST VI Guidance)

The VI Guidance provides a five-step process for evaluating whether the VI exposure pathway is complete and recommendations for completing a human health risk assessment, as well as mitigation measures, if necessary. The Petroleum UST VI Guidance considers the degradation of petroleum in the vadose zone and relies on separation distances to establish whether VI is a potentially complete exposure pathway.

ToxStrategies scientists and engineers have substantial experience addressing the vapor intrusion pathway. Example projects include modeling potential migration of vapors from the subsurface into building interiors, developing indoor air sampling plans, conducting indoor air sampling, developing applicable health-based screening levels, and assisting clients with community outreach.

Both documents can be found here.

The United States (US) Environmental Protection Agency (EPA) has been conducting a five-year, state-of-the-science assessment to determine the potential impacts of hydraulic fracturing activities on drinking water resources in the US. On June 4^th, EPA released an External Review Draft report, titled Assessment of the Potential Impacts of Hydraulic Fracturing for Oil and Gas on Drinking Water Resources.

The assessment found that “hydraulic fracturing activities have not led to widespread, systematic impacts to drinking water resources” but also “identifies important vulnerabilities to drinking water resources.”

ToxStrategies staff have been actively involved in assessing the potential human health impacts of natural gas exploration and production activities. Example projects include those involving conducting safety assessments for hydraulic fracturing fluids, assessing potential human health risks associated with impacts on ambient air, and assessing human health risks associated with accidental releases during drilling activities.

The full EPA report can be viewed here.