3. FOOD ChEMISTRy & bIOTEChNOLOGy 3.1. Lectures

Chem. Listy, 102, s265–s1311 (2008) Food Chemistry & Biotechnology
P57 ThE OCCuRENCE OF PhThALIC ACID
ESTERS IN SELECTED FEEDSTuFFS
LEnKA KRáTKá, ALŽBETA JAROŠOVá, JAnA
MALYSZOVá, VLASTA STAnCOVá and JIří
HARAZIM
Mendelova zemědělská a lesnická univerzita v Brně
Zemědělská 1, 613 00 Brno,
krtaska@seznam.cz
Introduction
Phthalate acid esters (PAEs) are used in large quantities as
softeners in many plastic products, paint, glue, putty, pharmaceutical
products and cosmetics. 1–3 Significant migration
into the environment is demonstrated during their production,
manufacture, use and disposal. 4–5 Phthalates are not chemically
bound to these products and are therefore continuously
released into the air or through leaching into liquids. 6–11
Humans can be exposed to vinyl plasticizers through ingestion,
inhalation, direct injection, or by skin contact. Exposures
to phthalates range from milligrams to micrograms 12 . The
occurrence of di-(2-ethylhexyl) phthalate (DEHP) ranks over
50 % of total PAEs. Butyl-benzyl phthalate (BBP) and di-nbutyl
phthalate (DBP) are common occurrence 13 .
Experimental
The aim of this investigation was to determine the occurance
and content of phthalate acid esters (DBP and DEHP)
in feedstuffs and oils.
M a t e r i a l
Samples of feedstuffs, premixes and feed additives for
livestocks were collected by qualified expert from ÚKZUZ
(Central Agricultural Control and Testing Institute) in years
2005 (n = 73) and 2006 (n = 59). These samples were collected
from received feeds, dispatch stores, reception stores
and multicomponent scales and stocked in polyethylene bags
and glass bottles. Samples of oils A, B, C (n = 23) were collected
during technological production processing in 2007.
Oils A were stored in glass bottles, B and C in plastic barrels.
M e t h o d s
Proved methods were used for PAEs determination in
feedstuffs 14 . Samples were stored in refrigerator after sampling
and transporting.
Before starting the analyses, glass and laboratory materials
were washed and rinsed with acetone. Samples were sufficiently
homogenized, extracted by organic solvents mixture
hexan:acetone (1 : 1). PAEs were separated from co-extracts
by GPC (gel permeation chromatography) in a Bio-beads S-
X3 filling. After GPC, the eluate was cleaned with hydrated
sulphuric acid. PAEs were determinated by HPLC and UV
detection at 224 nm in a Cogent e-Column, C 18, using acetonitrile:water
(9 : 1) as the mobile phase. The detection limit
for PAEs in feeds is 0.03 mg kg –1 .
s698
Table I
Concentrations of DBP, DEHP and ΣDBP + DEHP in feedstuffs
in 2005
Sample
DBP DEHP ΣDBP + DEHP
[mg kg –1 ] [mg kg –1 ] [mg kg –1 ]
Wheat 0.91 3.15 4.06
Soybean oil 110.96 20.46 131.42
natrium chloride 0.12 0.79 0.91
Vitamin K3 0.30 0.22 0.52
Vitamin D3 0.09 0.99 1.08
L-lysin < 0.03 < 0.03 < 0.03
Vegetable
soybean oil
19.89 8.60 28.49
Alimet-methionine 38.36 < 0.03 38.36
Animal fat 47.29 11.58 58.87
Animal fat 26.22 15.33 41.55
Folic acid 0.07 1.46 1.53
Corn 1.02 1.01 2.03
Results
Detected concentrations of DBP, DEHP and
ΣDBP + DEHP in the first year of study (2005) are digested
in Table I. The highest concentration of ΣDBP + DEHP
was found in soybean oil (131.42 mg kg –1 ) and animal fat
(58.87 mg kg –1 ). The lowest concentration was measured
for L-lysin (< 0.03 mg kg –1 ). In 2006 (n = 59) levels of
ΣDBP + DEHP ranged from 0.04 mg kg –1 (Wheat – start of
processing) to 32.4 mg kg –1 (Rapeseed oil – end. plastic).
A list of results in 2006 is given in Table II. PAEs in oils
are listed in Table III. The highest concentrations of PAEs
were measured in oils C (ΣDBP + DEHP = 61.55 mg kg –1 ),
whereas lowest levels were found in oils A (5.14 mg kg –1
ΣDBP + DEHP).
Table II
Concentrations of DBP, DEHP and ΣDBP + DEHP in feedstuffs
in 2006
Sample
DBP DEHP ΣDBP + DEHP
[mg kg –1 ] [mg kg –1 ] [mg kg –1 ]
Vitamin D3 0.08 0.28 0.36
Vitamin K3 < 0.03 0.19 0.19
Biotin 0.21 1.68 1.89
nicotinic acid 0.04 2.98 3.02
L-lysin 0.05 1.71 1.76
Vitamin E 0.62 1.53 2.15
Wheat - start of
processing
< 0.03 0.04 0.04
Rapeseed oil – start 2.43 18.55 20.98
Rapeseed oil – end 4.68 17.19 21.87
Rapeseed oil – end
plastic
26.63 5.77 32.4
Alimet 1.29 3.23 4.52
Mycocarb 0.05 0.04 0.09