Environmental fate of most commonly used pesticides in the Morava River Basin, Serbia

Svetlana Labus-Blagojević2, Veljko Gavrilović1, Nenad Dolovac1, Nened Trkulja, Erika Pfaf-Dolovac1

 

 

1 Institute for Pesticides and Environmental Protection, Teodora Drajzera 9, Belgrade, Serbia; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

2 Institute of Public Health of Serbia "Dr Milan Jovanović Batut", Dr Subotića 5, Belgrade, Serbia

 

 

 

Abstract

The Morava River Basin includes large surfaces of very fertile land suitable for producing cereal, vegetable and fruit crops. Such production requires considerable use of pesticides, as well as irrigation during dry summer months. In this work, the environmental fate of the most commonly used pesticides in the Morava River Basin: herbicides – atrazine and simazine, fungicides – zineb and chlorothalonil, and insecticides – lindane, endosulfan and dimethoate, is described according to available data from scientific literature. Analysis shows that intensive and long term use of pesticides can impact the environment in the Morava River Basin. However, there are no sufficient data about the environment in the Morava River Basin, and especially no integrative study covering all aspects of the environment in this area and providing guidelines for environmental safety and sustainable development. Due to the persistence of pesticides and their ability to reach water resources and affect living organisms and public health over a long period of time, an integrative monitoring approach is supported. Along with measurement of the presence, abundance and dispersion of pesticides in the environment, monitoring needs to include measurement of different parameters of the biota. Therefore, research teams must consist of professionals, specialists and scientists from different disciplines.

Keywords: Pesticides, insecticides, fungicides, herbicides, environmental fate, Morava River Basin

 

 

Introduction

The Morava River Basin includes large surfaces of very fertile land suitable for producing cereals, vegetables and fruits. There are also regions (Trstenik, Kruševac) where production of planting material (fruits and grapevines) is intensive. Such production requires considerable use of pesticides, as well as irrigation during dry summer months.

Herbicides. Atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) and simazine (6-chloro-N,N'-diethyl-1,3,5-triazine-2,4-diamine) have long been used to suppress broadleaf weeds in maize crops. They have been used as soil herbicides. This means that their effectiveness requires and depends on appropriate soil moisture levels. Bearing in mind the land use pattern in the Morava River Basin, it is only to be expected that certain amounts of these herbicides will end up in the river. This group of pesticides is applied only to maize, but their discharge into the river can negatively impact other crops through irrigation (Janjić, 1996).

Fungicides. Zineb (zinc-ethylene-bis-dithiocarbamate) is a fungicide used for the protection of vegetables against disease-causing agents. There is no specific mechanism of zineb action; it acts on a large number of phytopathogenic fungi, primarily the inducers of blight (Oomycetes group), as well as numerous inducers of leaf spot on vegetables (Alternaria, Septoria, etc.). It has been synthesized in Serbia since 1935 and has been traded and widely used for a long time. The production of zineb was terminated a couple of years ago and it is not registered as a fungicide any longer. One of the reasons for its withdrawal is the production of a very dangerous agent, ethylene-thiourea, during its degradation. Since vegetables are generally intensively irrigated, it can be assumed that there is a possibility of an increased presence of this preparation and/or its products in watercourses (Lyr, 1996).

During the past several years chlorothalonil (2,4,5,6-tetrachloroisophthalonitrile) has been extensively used for the protection of potato and some vegetables (onion, tomato, cucumber) from plant disease agents, especially of blight and leaf spot types. The problem associated with the use of chlorothalonil is the impurity of the preparation and the presence of several compounds produced during its synthesis: hexachlorobenzene and dioxin. Therefore, attention needs to be paid to their environmental fate and possible presence in watercourses (Tomlin, 2006).

Insecticides. Lindane (1r,2R,3S,4r,5R,6S)-1,2,3,4,5,6-hexachlorocyclohexane; γ-hexachlorocyclohexane, γ-HCH) is a very toxic insecticide, which has a long history as a plant protectant. It has been used as a foliar protector but also in granular form for application in soils. Endosulfan (6,7,8,9,10,10-Hexachloro-1,5,5a,6,9,9a-hexahydro- 6,9-methano-2,4,3-benzodioxathiepine-3-oxide) is a widely used insecticide but it is highly toxic to wild animals such that monitoring of the distribution of its residues in watercourses seems to be beneficial and important for environmental protection (Tomlin, 2000). Organophosphorous preparations have also been widely used in Serbia. Among a large number of other registered organophosphorous preparations, dimethoate (O,O-dimethyl S-methylcarbamoylmethyl phosphorodithioate) is the most commonly used. It has been used in vegetable and fruit crops to suppress pests, especially aphids and insects of the Diptera and Lepidoptera orders. Since it has been in use for a long time (Tomlin, 2000), it was chosen as the subject of this review.

Bearing in mind that the Morava River Basin is very important for drinking water supply and agriculture, the aim of this review is to explore possible environmental impacts that the above mentioned pesticides could have on the Morava River and the environment.