2, 4-D Residues in tubers; Texture and respiration of potatoes in storage

Development of a QuEChERS-Based Method for the Simultaneous Determination of Acidic Pesticides, Their Esters, and Conjugates Following Alkaline Hydrolysis

“…10 In potato tubers the increase following acidic hydrolysis was up to 6.8-fold. 25 Following alkaline hydrolysis of citrus fruit, the 2,4-D levels were reported to increase 1.6−2.1-fold in oranges, 28 2.4− 6.3-fold in grapefruit, and 2.8−5.7-fold in lemons. 29 In immature wheat plants MCPA levels were reported to increase 6-fold 24 after alkaline hydrolysis.…”

“…The authors noted a higher level of MCPA after alkaline hydrolysis compared to hydrolysis under acidic conditions. A second early study on incurred 2,4-D residues in potatoes tested acidic hydrolysis only and noted a significant enhancement of free 2,4-D . Nonextractable residues of 2,4-D in wheat straw and forage mainly released 2,4-D (free acid) by strong alkaline hydrolysis .…”

“…After applying acidic hydrolysis to immature cereal plants, 2,4-D levels increased 3-fold compared to the levels determined without hydrolysis . In potato tubers the increase following acidic hydrolysis was up to 6.8-fold . Following alkaline hydrolysis of citrus fruit, the 2,4-D levels were reported to increase 1.6–2.1-fold in oranges, 2.4–6.3-fold in grapefruit, and 2.8–5.7-fold in lemons .…”

Determination of free and hydrolyzable residues of 2,4-dichlorophenoxyacetic acid and 2,4-dichlorophenol in potatoes

“…Revenue et al (1963) reported that residue levels of 2.4-D in potatoes were very low using a method that involved the direct extraction of potatoes with an acidified organic solvent mixture. Using similar methodology, Nelson et al (1971) reported that potato samples boiled in 6 N H2S04 prior to extraction gave a 2-7-fold increase in the levels of 2,4-D found over those obtained by direct extraction with acidified benzene. Similar increases resulting from hydrolysis had been observed for residues of 2.4-D in beans (Thomas et al, 1963;Crosby, 1964) and in Forage (Yip and Ney, 1966).…”

“…In 1971, the federal registration covering the use of 2,4-dichlorophenoxyacetic acid (2,4-D on potatoes was in danger of cancellation for lack of adequate data. This plant growth regulator has been used as a foliar spray on potatoes for many years to intensify the skin color of red varieties and to reduce the yield of oversize tubers while increasing the yield of medium, more desirable tubers of all table stock varieties (Nelson and Nylund, 1963;Wort, 1965;Hegazy et al, 1978). To support this use, data on the resulting residues of 2,4-D and one of its possible metabolites, 2,4-dichlorophenol (2,4-DCP), had been requested by the U.S. Environmental Protection Agency.…”