Vol. 15—1961 - NorthEastern Weed Science Society

546.
A PRELIMINARYREPORTON THE EFFECT OF SOME
AQUATICHERBICIDES ON WATERQUALITyl
(Abstract)
by Samuel D. Faust 2, Robert
J. Tucker 3, and Osman Aly4
. Ester derivatives of 2,4-dichlorophenoxy acetic acid and
2(2.4,5-trichlorophenoxy) propionic acid have proven to be successful
aquatic herbicides. There are, however, several questions to be
answered concerning the effect of these compounds and their commercial
formulations on the quality of a potable water supply. Among these
questions are the following: Are there objectionable tastes and
odors imparted to the water? Do the commercial formulations effect
the chlorine demand of the water supply? Do these organic compounds
of phenolic origin release free phenols to the water? If so, what
are the mechanisms of release of these free phenols and how long do
these compounds persist? A report 1s offered, herewith, that provides
preliminary answers to these questions of the effect of aquatic
herbicides on water quality.
Various concentrations of two granular and one liquid formulation
of esters of 2,4-dichlorophenoxy acetic acid and one liquid formulation
of an ester of 2(2,4,5-trichlorophenoxy} propionic acid were added to
15 liter portions of a lake water. Each herbicide was added in concentrations
of'1,5, and 10 mg/l either as their acid equivalent or
as their ester equivalent. Thereupon these treated portions of
water and a control system were stored in five gallon carboys at
room temperature. Periodically these systems were examined for
threshold odor, chlorine demand, and free phenol content. ,All
analyses were made in accordance with the lOth edition of "Standard
Methods fbr the Examination of Water, Sewage, and Industrial Wastes",
American Public Health Association, 1955. In addition, the phenols
were also determined by another method described later in the report.
It was found that all four aquatic herbicides imparted objectionable
odors to the water at the three concentrations examined. The qualitative
description of the odor was a function of the herbicide carrier in the
commercial formulation. These odors were described as aromatic
(kerosene or fuel oil carriers) or musty (solid clay carriers). The
average threshold odor values ranged from 25 to 250 and, in general,
these values remained constant in all systems for storage periods
ranging from 50 to 75 days.
Ipaper of the Journal Series, New Jersey Agricultural Experiment
Station, Rutgers University, The State University of New Jersey,
Department of Sanitation, New Brunswick, N.J.
2Assistant Professor, Dept. of Sanitation, Rutgers University
3Re s ear ch Technician, Dept. of Sanitation, Rutgers University
4Research Assistant, Dept. of Sanitation, Rutgers University