SenesTech Answers Regarding ContraPest

The following questions were sent to SenesTech on June 23rd, 2017 regarding the safety of their ContraPest product. Their answers were sent in red, as you see below, 10+ weeks later, September 6th, 2017.

1. SenesTech came to Hana School on a reconnaissance trip to learn more about the degree of rat problem on the campus. You conducted tracking by using chew cards, plastic pieces using peanut butter as the attracting agent. Your findings of rat presence were not alarming.

Our team placed out chew cards (plastic cards baited with peanut butter) to determine where rats in and around the campus are comfortable foraging. We used tracking tiles (vinyl tiles covered with carpenter chalk) to determine where rats are running in and around the campus. 

2. SenesTech is directing all inquiries to State of Hawaii State Senator J. Kalani English through his executive assistant, Jacob.

Correct, per directions from the Senator’s office all questions should be sent to their office.

3. If I may, I’d like to clarify a few items with you. While I understand there is no potential project at Hana School presently I am curious as to the 1^stquarter Securities Exchange Commission (SEC) report that reads:

SenesTech Announces First Quarter Financial Results

Page 5, ¶8 : • In Hawaii, a project is underway to assess ContraPest as a blocking strategy for rapid rodent increases in sensitive island ecologies. If there is no potential project as you specified, please explain this reference above.

As Bandy and Ali mentioned during our meeting on July 6, 2017, a project is being conducted by a third party on Oahu using ContraPest in the island settings.

4. In addition, listed here are several questions I continue to seek answers to and plead now that you assist me in directing them to SenesTech personnel that can provide the answers if you are unable.What are the deal points of the pilot agreement? Where can we get a copy of the agreement?

We have not entered into any agreements.  

5. Given that it is fatal if absorbed through skin what precautions are being taken to ensure there is absolutely 0 contact with any children or humans in the area?

ContraPest is not fatal. The studies to demonstrate non-fatal status were in progress when the initial EPA registration approval was granted and product label was created. The label has since been updated to reflect exposure risk by toxicity data, which resulted in the ContraPest label wording changed from “Warning” (signal word associated with Category II products) to “Caution” (signal word associated with Category III products).

6. Where is any long-term safety data that we can look at?

There are no long-term safety or toxicology data regarding ContraPest for humans. The concentration of the active ingredients are very low (VCD- 0.09604%, Triptolid-0.00118%) in ContraPest. Because of the low concentration of active ingredients and the bait box delivery system, the Office of Pesticide Programs (OPP) stated, “human exposure to ContraPest is only expected to result from an accidental spill or mishandling. Because of this, no subchronic or chronic human exposure is anticipated, therefore, no subchronic or chronic toxicology studies were required” (EPA.gov, Registration Decision for the New Active Ingredients Triptolide and 4-Vinylcyclohexene diepoxide).7.

7. Where is long-term safety data regarding transient infertility in humans?

There are no long-term safety or toxicology data regarding ContraPest for humans. The concentration of the active ingredients are so low (VCD- 0.09604%, Triptolid-0.00118%) in ContraPest.

8. At what levels of exposure and/or absorption through skin will the product induce transient infertility in humans?

There is no data to indicate that ContraPest could be absorbed through the skin to provide an effective dose. We would not except accidental dermal exposure of ContraPest to induce transient infertility in humans. ContraPest requires repeated oral exposure to induce transient infertility in rats.

9. If other animals eat the product, where are the studies that show different species metabolize the product at the same rate as rats?

ContraPest is formulated for specifically for rats and the metabolism rates of ContraPest in other species is unknown. The bait box is designed for the feeding behavior and body size of rats, which deters or prevents other species from eating the product.  

10. What safety data has been gathered to show that the sperm destroying capability of triptolide only affects the sperm of rats?

Triptolide, given at the correct dose and length of exposure for the target species, would be expected to affect sperm production in other species. We have studies underway in other pest species with the goal to provide safe, non-lethal pest control of these animals too.

11. Given that the compound quickly breaks down into inactive ingredients when it hits soil or water, what data do we have that shows the extremely high moisture levels of Hana and the constant rain will not make the product inactive?

Contrapest is packaged in plastic tanks and deployed in a locked bait boxes which are designed to contain and shelter ContraPest from weather exposure. We would not anticipate heavy rains or high humidity to inactive ContraPest inside the bait box.

12. What exactly in soil causes the compound to break down quickly into inactive ingredients? And how are we sure that that item is not all over Hana?

The product is confined in a tamper-resistant bait box to ensure it remains contained. The primary containment is the reservoir tank and the secondary containment is the bait box itself.

If the product did come into contact with soil, it begins breaking down because of the reactive functional groups in the active ingredients. The epoxide groups present in each active ingredient, and also the hydroxyl in triptolide, react with the abundant carbon and nitrogen rich organic compounds in soil. These functional groups are also what make each active ingredient biologically active. Thus, when they are lost when they react with organic compunds, ContraPest is no longer effective.

13. All studies submitted show reductions in populations for 12 week periods; what long-term studies have been done to show that the reduction in population is permanent or semi permanent?

We have not had the opportunity to conduct long term studies using ContraPest. The longest field study we have conducted to date was a 19-week urban study in the Northeastern United States. This study demonstrated that ContraPest suppressed the rat population compared to untreated rats.

14. What studies using this compound has been completed in an area like Hana where the majority of the rat population is outdoors?

We have not had the opportunity to use ContraPest in an environment like Hana. A project is currently being conducted by a third party on Oahu to look at the effects of ContraPest on black rats in jungle environments. This project will provide early information on understanding the black rat’s feeding activity and how to optimally deploy ContraPest in these environments. 

We have conducted several studies in urban areas and in an agricultural area, in which the rats lived both indoors and outdoors. The results of these studies demonstrated that ContraPest suppressed the rat populations in these areas.

15. Given that the product can only be used indoors, and the majority of the rat population in Hana is outdoors, what data and evidence do we have that shows an indoor product such as this creates a lasting population effect in an outdoor/field population. Where can I find the studies that prove giving a chemical compound indoors to rats whose population is largely outdoors, the compound does not become evident in outside environments?

Per the label, ContraPest is approved for indoor and outdoor use within 1 ft. of a man-made structure. See question 12 for inactivation of ContraPest in soil.

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See more info in the Facebook working group: No Fatal Poisons at Hana School