UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON D.C., 20460

Chemical Code: 036602

DP Barcode: DP347416

December 12, 2007

MEMORANDUM

SUBJECT:	EFED’s Calculation of Acute Risk Quotients for Freshwater and
Marine Estuarine Fish Based on the Upgraded Mandipropamid Fish Toxicity
Studies.

TO:			Tony Kish, Risk Manager

Registration Division (7505P)

FROM:		Fred Jenkins, Biologist

Environmental Fate and Effects Division

THROUGH:		Dana Spatz, Acting Branch Chief

Environmental Risk Branch II

Environmental Fate and Effects Division (7507P)

Previously Syngenta requested a classification upgrade (from
unacceptable to acceptable) of several acute fish toxicity studies
testing mandipropamid, including MRID’s 468001-03, 468001-04,
468001-05, and 468001-06.  EFED agreed with Syngenta’s rationale and
request in a memo dated October 19, 2007: “EFED’s Response to
Syngenta’s Request to Upgrade Several Mandipropamid Aquatic Toxicity
Studies, DP Barcode D345152.”  

Now that these studies are considered scientifically valid and
acceptable, they can be used in an  ecological risk assessment.  The
RQ’s resulting from these additional endpoints are included below.  We
note that these studies do not indicate any additional risks of concern
to those discussed in EFED’s Screening Level Ecological Risk
Assessment for Mandipropamid dated  July 24, 2007.    

According to the acute RQ values for freshwater and marine estuarine
fish (Table 1), mandipropamid does not pose a risk to freshwater or
marine/estuarine fish, above the Agency’s Level of Concern.  The RQs
were calculated based on the most sensitive species tested.

Table 1. Acute RQs for Fish Exposed to Mandipropamid including its
degradate of toxic concern, SYN500003 and SYN504851.



Measure of Effect(Test Species)	Toxicity

Value

(ppm)	EEC Peak (ppm)	Acute RQ

(EEC/Toxicity Value)

Freshwater Fish (Rainbow trout)	96-h LC50 4.4 	0.021	0.005 *

Marine/Estuarine Fish (Sheepshead minnow)	96-h LC50 4.5	0.021	0.005 *

* Does not exceed acute endangered species LOC of 0.05 or acute LOC of
0.1



 PAGE   

 PAGE   2 

OFFICE OF

PREVENTION, PESTICIDES AND

TOXIC SUBSTANCES

