Case-control Study of Risk Factors for Lumbar Intervertebral Disc Herniation in Croatian Island Populations

Aim: To investigate the risk factors for lumbar intervertebral disc herniation (L4/L5 or L5/S1) severe enough to require surgery of the lower spine among 9 isolated populations of Croatian islands and to evaluate predictive value, sensitivity, and specificity of a simple screening test based on the understanding of the risk factors in this population. Methods: In a sample of 1001 examinees from Croatian island populations, we identified all subjects who underwent surgery of the lower spine due to lumbar intervertebral disc herniation L4/L5 or L5/S1 and selected 4 controls matched by age, gender, and village of residence for each of them. Odds ratio was computed for the following variables: body mass index, occupation, intensity of physical labor at work, intensity of physical labor at home, smoking index, claudication index, self-assessed limitation in physical activity, level of education, socio-economic status, and family history of lumbar intervertebral disc herniation requiring surgery. Results: Comparison of 67 identified cases with 268 controls revealed the highest odds ratios (OR) for positive family history (OR 4.00; 95% confidence intervals [CI], 1.89-6.11, P<0.001), intensity of physical labor at work defined as “hard” (OR 2.94; 95% CI, 1.07-4.81, P<0.001), and body mass index of 25.7 or more (OR 2.77, 95% CI, 1.05-4.49, P=0.002). A simple screening test based on the presence of any two of these three criteria has 74% sensitivity and 82% specificity to detect persons who underwent lower spine surgery due to lumbar intervertebral disc herniation in the population aged 40 years or more. Conclusion: Occurrence of lumbar disk herniation severe enough to require surgery of the lower spine can be predicted using a very simple set of criteria. This type of screening could reduce the need for surgery in isolated communities through prevention within primary health care

The Role of Fruit Drinks in Daily Diet of Some Osijek Inhabitants, Croatia

The aim of the study was to assess the role of fruit drinks in daily diet of Osijek inhabitants. A special questionnaire was administered to 199 patients visiting a family physician’s office during December 2003. The concentration of vitamin C (L-ascorbic acid) was determined in 42 commercially available fruit drinks. Only 11% (22/199) of study subjects did not take fruit drinks. The mean concentration of vitamin C in all samples was 150.10166.83 mg/L. The questionnaire revealed that 89% (177/199) of study subjects using fruit drinks were taking a mean of 0.4 L of fruit drink per day, yielding a mean of 60.04 mg of vitamin C, i.e. 100% of the recommended daily allowance of 60 mg. Study results indicated fruit drinks to be a significant source of vitamin C in daily diet, however, great variation in vitamin C intake according to socioeconomic status of study subjects and type of fruit drink should be noted

Demonstrating Reduced Environmental and Genetic Diversity in Human Isolates by Analysis of Blood Lipid Levels

Aim: To test the hypothesis that phenotypic diversity in isolated human populations is decreased in comparison with general outbred population because of reduced genetic and environmental diversity. To demonstrate this in populations for which reduced genetic and environmental diversity had already been established, by studying the amount of variation in plasma lipid levels. Methods: Fasting plasma lipid levels (cholesterol, triglycerides, low density lipoprotein [LDL], and high density lipoprotein [HDL]) were measured in randomly selected 300 inhabitants from 2 isolated human populations, the island of Rab and the neighboring islands of Vis and Lastovo, Croatia. The populations were chosen based on previous analyses of genetic diversity and lifestyle patterns, which were shown to be both less diverse and more uniform than the general Croatian population. We studied whether the 25’-75’ and 5-95’ interpercentile ranges in observed values were consistently smaller in 2 samples of 300 examinees from isolated populations in comparison with nearly 6000 examinees from an earlier study who were demographically targeted to represent the larger Croatian population. Results: General population had much wider range of observed values of triglycerides and HDL than both isolated populations. However, both isolated populations exhibited greater extent of variation in the levels of LDL, while the ranges of cholesterol values were similar. Conclusion: Although reduced genetic and environmental diversity in isolated human populations should necessarily reduce the variance in observed phenotypic values, it appears that specific population genetic processes in isolated populations could be acting to maintain the variation. Departure from the Hardy-Weinberg equilibrium due to consanguinity, sub-structuring and differentiation within the isolates, and increased rate of new mutations could theoretically explain this paradox

Organoklorirani pesticidi u slatkovodnim ribama zagrebačkog područja

The aim of this study was to determine the level of organochlorine pesticides in freshwater fish from the Zagreb area, Croatia. The study included 215 freshwater fish samples from three sites: the Sava River, Lake Jarun, and five fishponds from the Zagreb surroundings. Organochlorine pesticides DDT and derivates, HCH, HCB, lindane, aldrin, dieldrin, endrin, heptachlor with epoxide, and methoxychlor were determined using the GC-ECD method. The determined amounts of organochlorine pesticides were within allowed concentration limits in all analysed fish samples. Median values ranged from below the detection limit of 0.01 µg kg-1 for dieldrin and metoxychlor to 2.00 µg kg-1 for DDT in the Cyprinidae fish family from the Sava River, Zagreb sampling site (group 1). This study has confirmed pesticide persistence in the overall ecosystem in our country despite the ban of some thirty years ago, like in many other parts of the world.Cilj istraživanja bio je utvrditi količinu organokloriranih pesticida u slatkovodnim ribama zagrebačkog područja. Obrađeno je ukupno 215 uzoraka slatkovodne ribe sa sljedećih triju lokacija: rijeka Sava, jezero Jarun i pet tzv. ekoloških jezera u okolici Zagreba. Organoklorirani pesticidi DDT i derivati, HCH izomeri (α-HCH, β-HCH and δ-HCH), HCB, lindan (γ-HCH), aldrin, dieldrin, endrin, heptaklor, heptaklorepoksid i metoksiklor) određivali su se metodom plinske kromatografije uz elektronapsorpcijski način detekcije i uz postignutu granicu detekcije od 0,01 µg kg-1. Vrijednosti ispitivanih organokloriranih pesticida u svim su uzorcima riba bile mnogo niže od maksimalno dopuštenih koncentracija. Vrijednosti medijana kretale su se od najnižih 0,01 µg kg-1 za dieldrin i metoksiklor do najviših 2,00 µg kg-1 za DDT u uzorcima riba porodice Cyprinidae s lokacije Sava - Zagreb. Utvrđeni ostaci preostalih ispitivanih pesticida potvrđuju kako njihovu uporabu na našim područjima tako i njihovu postojanost i prisutnost u cjelokupnom ekosustavu unatoč činjenici da je većina zabranjena u Hrvatskoj prije gotovo 30 godina, kao i u mnogim dijelovima svijeta

Case-control Study of Risk Factors for Lumbar Intervertebral Disc Herniation in Croatian Island Populations

Aim: To investigate the risk factors for lumbar intervertebral disc herniation (L4/L5 or L5/S1) severe enough to require surgery of the lower spine among 9 isolated populations of Croatian islands and to evaluate predictive value, sensitivity, and specificity of a simple screening test based on the understanding of the risk factors in this population. Methods: In a sample of 1001 examinees from Croatian island populations, we identified all subjects who underwent surgery of the lower spine due to lumbar intervertebral disc herniation L4/L5 or L5/S1 and selected 4 controls matched by age, gender, and village of residence for each of them. Odds ratio was computed for the following variables: body mass index, occupation, intensity of physical labor at work, intensity of physical labor at home, smoking index, claudication index, self-assessed limitation in physical activity, level of education, socio-economic status, and family history of lumbar intervertebral disc herniation requiring surgery. Results: Comparison of 67 identified cases with 268 controls revealed the highest odds ratios (OR) for positive family history (OR 4.00; 95% confidence intervals [CI], 1.89-6.11, P<0.001), intensity of physical labor at work defined as “hard” (OR 2.94; 95% CI, 1.07-4.81, P<0.001), and body mass index of 25.7 or more (OR 2.77, 95% CI, 1.05-4.49, P=0.002). A simple screening test based on the presence of any two of these three criteria has 74% sensitivity and 82% specificity to detect persons who underwent lower spine surgery due to lumbar intervertebral disc herniation in the population aged 40 years or more. Conclusion: Occurrence of lumbar disk herniation severe enough to require surgery of the lower spine can be predicted using a very simple set of criteria. This type of screening could reduce the need for surgery in isolated communities through prevention within primary health care

Migration of Phthalates from Plastic Containers into Soft Drinks and Mineral Water

The aim of this study was to determine the level of phthalate migration from plastic containers to soft drinks and mineral water and to identify a possible relationship between the amount and type of phthalate migration, type of preservative used, and the pH of the sample. The analysis included 45 samples of products packed in containers made from polyethylene terephthalate. The samples were divided into 5 groups: group 1 (N=9), soft drinks preserved with orthophosphoric acid; group 2 (N=14), soft drinks preserved with Na-benzoate; group 3 (N=5), soft drinks preserved with K-sorbate; group 4 (N=8), soft drinks preserved with a combination of Na-benzoate and K-sorbate; and group 5 (N=9), mineral water without preservatives. The samples were analyzed by the method of gas chromatography, with a detection limit of 0.005 μg/L. The mean pool phthalate level and mean pH value were 91.67 μg/L and 2.82±0.30 in group 1; 116.93 μg/L and 2.75±0.32 in group 2; 819.40 μg/L and 2.88±0.15 in group 3; 542.63 μg/L and 2.82±0.54 in group 4; and 20.22 μg/L and 5.82±1.26 in group 5, respectively. The highest rate of migration to soft drinks was recorded for dimethyl phthalate, ranging from 53.51 to 92.73 %, whereas dibutyl phthalate and diethylhexyl phthalate showed highest rate of migration to the mineral water (56.04 and 43.42 %, respectively). The highest level of phthalate migration from plastic containers to soft drinks was found in the products preserved with K-sorbate. The rate of phthalate migration appears to be influenced also by the drink pH, i.e. the lower the pH value, the greater the phthalate migration. Dimethyl phthalate showed highest migration to preserved drinks as an acidic medium, which might stimulate modification in the composition of plastic containers according to the type and composition of the product. Additional studies in a greater number of samples are needed. Although the phthalate levels measured in these samples pose no risk for human health, it should be borne in mind that the accumulation of small individual amounts taken with time may increase the lifelong phthalate exposure and eventually threaten the exposed person’s life

Demonstrating Reduced Environmental and Genetic Diversity in Human Isolates by Analysis of Blood Lipid Levels

AIM: To test the hypothesis that phenotypic diversity in isolated human populations is decreased in comparison with general outbred population because of reduced genetic and environmental diversity. To demonstrate this in populations for which reduced genetic and environmental diversity had already been established, by studying the amount of variation in plasma lipid levels. ----- METHODS: Fasting plasma lipid levels (cholesterol, triglycerides, low density lipoprotein [LDL], and high density lipoprotein [HDL]) were measured in randomly selected 300 inhabitants from 2 isolated human populations, the island of Rab and the neighboring islands of Vis and Lastovo, Croatia. The populations were chosen based on previous analyses of genetic diversity and lifestyle patterns, which were shown to be both less diverse and more uniform than the general Croatian population. We studied whether the 25'-75' and 5'-95' interpercentile ranges in observed values were consistently smaller in 2 samples of 300 examinees from isolated populations in comparison with nearly 6000 examinees from an earlier study who were demographically targeted to represent the larger Croatian population. ----- RESULTS: General population had much wider range of observed values of triglycerides and HDL than both isolated populations. However, both isolated populations exhibited greater extent of variation in the levels of LDL, while the ranges of cholesterol values were similar. ----- CONCLUSION: Although reduced genetic and environmental diversity in isolated human populations should necessarily reduce the variance in observed phenotypic values, it appears that specific population genetic processes in isolated populations could be acting to maintain the variation. Departure from the Hardy-Weinberg equilibrium due to consanguinity, sub-structuring and differentiation within the isolates, and increased rate of new mutations could theoretically explain this paradox

Migracija ftalata iz plastičnih boca u negazirana pića i mineralnu vodu

The aim of this study was to determine the level of phthalate migration from plastic containers to soft drinks and mineral water and to identify a possible relationship between the amount and type of phthalate migration, type of preservative used, and the pH of the sample. The analysis included 45 samples of products packed in containers made from polyethylene terephthalate. The samples were divided into 5 groups: group 1 (N=9), soft drinks preserved with orthophosphoric acid; group 2 (N=14), soft drinks preserved with Na-benzoate; group 3 (N=5), soft drinks preserved with K-sorbate; group 4 (N=8), soft drinks preserved with a combination of Na-benzoate and K-sorbate; and group 5 (N=9), mineral water without preservatives. The samples were analyzed by the method of gas chromatography, with a detection limit of 0.005 μg/L. The mean pool phthalate level and mean pH value were 91.67 μg/L and 2.82±0.30 in group 1; 116.93 μg/L and 2.75±0.32 in group 2; 819.40 μg/L and 2.88±0.15 in group 3; 542.63 μg/L and 2.82±0.54 in group 4; and 20.22 μg/L and 5.82±1.26 in group 5, respectively. The highest rate of migration to soft drinks was recorded for dimethyl phthalate, ranging from 53.51 to 92.73 %, whereas dibutyl phthalate and diethylhexyl phthalate showed highest rate of migration to the mineral water (56.04 and 43.42 %, respectively). The highest level of phthalate migration from plastic containers to soft drinks was found in the products preserved with K-sorbate. The rate of phthalate migration appears to be influenced also by the drink pH, i.e. the lower the pH value, the greater the phthalate migration. Dimethyl phthalate showed highest migration to preserved drinks as an acidic medium, which might stimulate modification in the composition of plastic containers according to the type and composition of the product. Additional studies in a greater number of samples are needed. Although the phthalate levels measured in these samples pose no risk for human health, it should be borne in mind that the accumulation of small individual amounts taken with time may increase the lifelong phthalate exposure and eventually threaten the exposed person’s life.Svrha je ovog istraživanja bila odrediti razinu migracije ftalata iz plastičnih boca u negazirana pića i mineralnu vodu te odrediti mogući odnos količine i tipa migracije ftalata, tipa konzervansa i pH-vrijednosti uzorka. Analizirano je 45 uzoraka proizvoda pakiranih u boce izradene od polietilen-tereftalata (PET ambalaža). Uzorci su podijeljeni u 5 skupina: skupina 1 (N=9), negazirana pića s ortofosfornom kiselinom kao konzervansom; skupina 2 (N=14), negazirana pića s Na-benzoatom; skupina 3 (N=5), negazirana pića s K-sorbatom; skupina 4 (N=8), negazirana pića s kombinacijom Na-benzoata i K-sorbata i skupina 5 (N=9), mineralna voda bez dodatka konzervansa. Uzorci su analizirani plinskom kromatografijom s razinom detekcije od 0,005 μg/L. Srednja vrijednost ukupnog iznosa ftalata i pH-vrijednosti iznosila je 91,67 μg/L i 2,82±0,3 u skupini 1; 116,93 μg/L i 2,75±0,32 u skupini 2; 819,40 μg/L i 2,88±0,15 u skupini 3; 542,63 μg/L i 2,82±0,54 u skupini 4 i 20,22 μg/L i 5,82±1,26 u skupini 5. U negaziranim pićima pronađeno je najviše dimetilftalata, od 53,51 do 92,73 %, a u mineralnoj vodi najviše dibutil- i dietilheksilftalata (od 56,04 i 43,42 %). Najveća količina ftalata pronađena je u negaziranim pićima konzerviranim K-sorbatom. Migracija ftalata najvjerojatnije je uzrokovana pH-vrijednošću pića, tj. što je niža pH-vrijednost, veća je migracija ftalata. Dimetilftalat najviše je migrirao u zakiseljena pića koja, ovisno o svom tipu i sastavu, uzrokuju promjenu sastava plastičnih boca. Potrebno je provesti dodatna istraživanja većeg broja uzoraka. Iako izmjerene količine ftalata ne predstavljaju opasnost za zdravlje, treba imati na umu da s vremenom nakupljeni ftalati mogu ugroziti ljudski život