What’s Up with Endosulfan? Field Vegetable Edition

Denise Beaton, OMAF and MRA Crop Protection Program Lead; Marion Paibomesai, OMAF and MRA Vegetable Specialist – This article has been adapted specific to field vegetables (excluding potatoes) with excerpts from the original article in Hort Matters Volume 13, Issue 25 in December 2013.

Lately, we have received many questions about endosulfan, mainly on which products and uses are still registered. There is a lot of confusion right now. We’ll try to answer the “who, what, where, when, why” so we are all on the same page.

To provide a bit of background, Health Canada’s Pest Management Regulatory Agency (PMRA) conducted a re-evaluation of endosulfan uses in Canada. In 2010, they determined that all uses of endosulfan could no longer be supported. Through consultation with stakeholders, uses that had no alternatives to endosulfan were identified. These uses were given a longer-term phase-out to provide more time to find alternatives. In February 2011, PMRA communicated the phase-out dates for endosulfan products and the mitigation measures required to further protect workers and the environment, which is found in their consultation document titled REV2011-01, Discontinuation of Endosulfan.

As per, REV2011-01, Discontinuation of Endosulfan – Appendix I

Last date of use is December 31, 2010 on the following crops:

• All product formulations: spinach, succulent beans, succulent peas;
• WP product formulation: above crops and field tomatoes, sweet corn.

Last date of use is December 31, 2012 on the following crops/sites:

• broccoli, Brussels sprouts, cabbage, cauliflower, sweet corn, rutabaga, turnip, bait station outside food processing plants.

Last date of use is December 31, 2016 on the following crops:

• celery, field cucumber, eggplant, head lettuce, melon, pepper, pumpkin, squash, sugarbeet, field tomato (excluding WP formulations, since this registered use expired in 2010).

To complicate things a bit, the registrations for some endosulfan products already expired prior to the last phase-out date in 2016. For example, the registration for Thiodan 50 WP (PCP# 15821) expired on December 31, 2012; Thionex 50W (PCP# 14617) expired as of July 1, 2013; and, Thiodan 4EC (PCP# 15747) expired on December 31, 2013. These products cannot be used in the 2014 growing season.

To help clarify the situation, the following table shows the endosulfan products that can be used on specific crops and provides the date it can legally be used. However, please consult the most current labels for full label directions and precautions.

Emulsifiable Concentrate Formulations (EC)  Thionex EC (PCP# 23453) – Last Date of Use is December 31, 2016
Crop	Activity	Restricted Entry Interval	Pre-Harvest Interval	Maximum # of Applications
Celery	All activities	4 days	14 days	1
Head Lettuce	All activities	4 days	14 days	2 (minimum 7 day spray interval)
Field Cucumber, Melon	All activities	4 days	9 days	3 (minimum 7 day spray interval)
Pumpkin, Squash	All activities	7 days	9 days	3 (minimum 7 day spray interval)
Eggplant, Pepper, Field Tomato	All activities	4 days	27 days	2 (minimum 7 day spray interval)
Sugarbeet	Irrigation, scouting	10 days	45 days	1
	Other activities	2 days
Wettable Powder Formulations  Thionex 50W-WSP (PCP# 29990) – Last Date of Use is December 31, 2016
Crop	Activity	Restricted Entry Interval	Pre-Harvest Interval	Maximum # of Applications
Celery	All activities	4 days	17 days	1
Head Lettuce	All activities	4 days	17 days	2 (minimum 7 day spray interval)
Field Cucumber, Melon	All activities	4 days	13 days	2 (minimum 7 day spray interval)
Pumpkin, Squash	Hand weeding, pruning, hand thinning	12 days	13 days	2 (minimum 7 day spray interval)
	Other activities	10 days
Eggplant, Pepper	All activities	9 days	27 days	2 (minimum 7 day spray interval)

Adapted from:  REV2011-01, Discontinuation of Endosulfan – Appendix I

After December 31, 2016, no endosulfan products can be used in Canada (or anywhere in the world). There was a global decision made at the Stockholm Convention in April 2011 to phase out endosulfan by 2017. Endosulfan is on the United Nation’s list of persistent organic pollutants. For more information, you can visit the PMRA website at www.hc-sc.gc.ca/cps-spc/pest/index-eng.php.