An investigation of some persistent organic pollutants in loggerhead sea turtles (Caretta caretta).

The study assessed persistent organic pollutants (POPs) in Caretta caretta turtles along Turkish coasts, analyzing bioaccumulation in accessible organs and discerning sex-related differences. Ten adult turtles (5 males, 5 females) from Mugla province were sampled post-mortem. Various tissues were analyzed for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and polycyclic aromatic hydrocarbons (PAHs) using gas chromatography-mass spectrometry. DDT distribution showed no sex-based difference, with concentrations highest in fat tissue followed by liver, kidney, muscle, spleen, and heart. Male PCB concentrations ranked highest in fat, followed by kidney, liver, spleen, muscle, and heart, while females showed a similar trend. PAH concentrations were highest in fat for both sexes, followed by various organs. Limited PBDE concentrations hindered comprehensive evaluation. Overall, C. caretta act as effective bioindicators for monitoring environmental pollution, with certain POPs exhibiting sex and organ-based variations.

Toward understanding the role of the interstitial tissue architects: Possible functions of telocytes in the male gonad.

Telocytes represent a relatively recently discovered population of interstitial cells with a unique morphological structure that distinguishes them from other neighboring cells. Through their long protrusions extending from the cell body, telocytes create microenvironments via tissue compartmentalization and create homo- and hetero-cellular junctions. These establish a three-dimensional network enabling the maintenance of interstitial compartment homeostasis through regulation of extracellular matrix organization and activity, structural support, paracrine and juxtracrine communication, immunomodulation, immune surveillance, cell survival, and apoptosis. The presence of telocytes has also been confirmed in testicular interstitial tissue of many species of animals. The objective of this review is to summarize recent findings on telocytes in the male gonad, on which conclusions have been deduced that indicate the involvement of telocytes in maintaining the cytoarchitecture of the testicular interstitial tissue, in the processes of spermatogenesis and steroidogenesis, and photoperiod-mediated changes in the testes in seasonally reproductive animals.

Elevated luteinizing hormone receptor signaling or selenium treatment leads to comparable changes in adrenal cortex histology and androgen-AR/ZIP9 signaling.

The importance and regulation of adrenal androgen production and signaling are not completely understood and are scarcely studied. In addition, there is still a search for appropriate animal models and experimental systems for the investigation of adrenal physiology and disease. Therefore, the main objective of the study was to evaluate the effect of luteinizing hormone (LH) signaling and selenium (Se2+) exposure on androgen adrenal signaling via canonical androgen receptor (AR), and membrane androgen receptor acting as zinc transporter (zinc- and iron-like protein 9; ZIP9). For herein evaluations, adrenals isolated from transgenic mice with elevated LH receptor signaling (KiLHRD582G) and adrenals obtained from rabbits used for ex vivo adenal cortex culture and exposure to Se2+ were utilized. Tissues were assessed for morphological, morphometric, and Western blot analyses and testosterone and zinc level measurements.Comparison of adrenal cortex histology and morphometric analysis in KiLHRD582G mice and Se2+-treated rabbits revealed cell hypertrophy. No changes in the expression of proliferating cell nuclear antigen (PCNA) were found. In addition, AR expression was decreased (p < 0.001) in both KiLHRD582G mouse and Se2+-treated rabbit adrenal cortex while expression of ZIP9 showed diverse changes. Its expression was increased (P < 0.001) in KiLHRD582G mice and decreased (P < 0.001) in Se2+-treated rabbits but only at the dose 10 ug/100 mg/ tissue. Moreover, increased testosterone levels (P < 0.05) and zinc levels were detected in the adrenal cortex of KiLHRD582G mice whereas in rabbit adrenal cortex treated with Se2+, the effect was the opposite (P < 0.001).

Silk fibroin nanoparticles and ß-tricalcium phosphate loaded tissue engineered gelatin bone scaffolds: A Nature-based, low-cost solution.

Tissue engineering has recently attracted attention as an alternative to traditional treatment methods for tissue and organ damage. Since bone is one of the most important vital parts of the body, the treatment of bone damage is important. Silk fibroin is a natural polymer with properties such as biocompatibility and biodegradability, which attracts attention with its controlled release, especially in drug delivery systems. In this study, gelatin-based scaffolds loaded with silk fibroin nanoparticles and ß -tricalcium phosphate (ß -TCP) were developed to be used as a potential drug delivery system in bone tissue engineering. The chosen nanoparticle formulation has a 294 nm average diameter with a 0.380 polidispersity index (PDI). In vitro characterization of scaffolds was performed by mechanical, morphological characterization, swelling capacity, Differential Scanning Calorimetry (DSC), Fourier-Transform Infrared Spectroscopy (FT-IR) measurements, and biocompatibility was evaluated by cell culture studies. Swelling index, tensile strength, elongation at break, and Young modulus of the ß -TCP and silk nanoparticles loaded scaffold were found as 456%, 1.476 MPa, 6.75%, and 24 MPa, respectively. In vitro cell culture studies have shown that scaffolds prepared in the present study can accelerate osteoblast differentiation and increase the healing rate of bone tissues. In addition, they have the potential to be used as a drug delivery system in bone tissue engineering that needs to be evaluated with further studies.

Live in same region, respond differently: Canine and human response to pollutants in placental accumulation.

Polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs), and polycyclic aromatic hydrocarbons (PAHs) are endocrine-disrupting chemicals (EDCs). Their presence in the environment is particularly concerning in cases of fetal exposure, which is the most vulnerable period of life for both human and animals who share the same environment. Placenta, as a sample collected using noninvasive methods to screen EDCs, is a good indicator for potential fetal exposure. Although recent studies indicate that companion animal may correspond to human exposure, species-specific anatomo-morphological and metabolic differences are controversial. In this study, placenta samples of 60 women and 25 dogs living and giving birth within the same region were evaluated for the presence of PCB, OCP, PBDE, and PAH residues; where, socio-demographic factors were also assessed to identify the possible sources. Gas chromatography-mass spectrometry method was validated for the matrix, and among 45 screened and targeted pollutants, only 18 were found in human placentas. While the most frequently detected pollutants were DDTs, followed by PAHs and PCBs in decreasing order, the pollutants with the highest concentrations were PAHs, followed by PCBs and DDTs. Only five of the target contaminants were detected in the dog placentas. These results indicate that; as dogs have different bioaccumulation capacities and higher excretion rates than humans, the life-long effects of exposure to endocrine compound and possible consequences related to adverse health outcomes are expected to vary and concentrations cannot be directly correlated.

Diethylhexyl Phthalate and Bisphenol A Promote Vincristine and Tamoxifen Resistance in Vitro.

Environmental estrogen active compounds are strong determinants of estrogen receptor (ER)-positive breast cancers, and increased evidence indicates their contribution to chemotherapy resistance. In the current study, the efficacy of vincristine and tamoxifen, with the presence of diethylhexyl phthalate (DEHP) and bisphenol A (BPA) and the possible involvement of estrogen and estrogen receptor-related mechanisms, was evaluated in an ER+ mammary tumor cancer cell line, MCF-7. Chemotherapeutics tamoxifen as an estrogen receptor modulator and vincristine as an antimitotic compound were selected for evaluation against the presence of common endocrine disrupters. BPA and DEHP preincubation at their proliferative concentrations for 4 h was found to decrease the cytotoxicity of vincristine. mRNA and protein expression of ESR1 and ESR 2 were decreased by vincristine, while this decrease was reversed by DEHP and BPA. Both BPA and DEHP were able to interfere with the cytotoxic activity of vincristine against MCF-7 cells through ESR1 and ESR2. This study provides in vitro toxicological evidence for vincristine resistance and its relation to estrogen active environmental pollutants in ER+ breast cancer cells.

Effects of electrospun fiber curcumin on bisphenol A exposed Caco-2 cells.

Curcumin; the major polyphenolic compound, isolated from Curcuma longa L.; loaded polyvinylpyrrolidone K90 fibers were prepared using electrospinning method. Effectiveness was tested on human colorectal adenocarcinoma cells with the presence of the endocrine disrupter Bisphenol A. Curcumin-loaded fibers were shown to have good physicochemical properties where excellent morphology of the electrospin fibers were formed. With the presence of 8 nM Bisphenol A, 17.37 mM fibers were found to inhibit proliferation in the cells in a dose-dependent manner. Fibers induced a significant increase in malondialdehyde by Thiobarbituric Acid Reactive Substances Assay compared to the control and this effect was supported by the presence of Bisphenol A. Western blot results indicate Super Oxide Dismutase-1 levels were increased by fiber, while Bisphenol A coincubated group resulted in a decrease. Fibers increased the expression of Estrogen Receptor 2, while Estrogen Receptor 1 expression did not change. Estrogen Receptor 2 expression was increased by coincubation with Bisphenol A; indicating a possible role of Estrogen Receptor 2 in the protective effects of fiber. This study presents that fiber had enhanced bioavailability and solubility with increased anticancer effect in human colon adenocarcinoma cells in presence of Bisphenol A; where involved mechanisms are antioxidant system and estrogen receptor expression.

Multiresidues of environmental contaminants in bats from Turkey.

Bat populations have been steadily declining, most likely because of anthropogenic factors. Identification and classification of these risks have crucial importance in ensuring the survival of this species. Bats often coexist with humans in urban, industrial, and agricultural areas and are potentially exposed to a range of environmental pollutants. Two bat species widely distributed in Turkey were selected, and the residues of pesticides and organic contaminants in their carcasses were analyzed using: gas chromatography-mass spectrometry, gas chromatography-tandem mass spectrometry, and liquid chromatography-tandem mass spectrometry. Species and sex specific differences were evaluated along with their potential to be used as bioindicators. During the rigor mortis period, 23 adult Pipistrellus pipistrellus (11 female and 12 male) and 19 adult Myotis myotis (9 female and 10 male) were collected and 322 contaminants (pesticides and organic contaminants) were analyzed in whole carcasses of bats by using a validated method. Multiple pesticides and organic contaminants were detected in all collected 42 bats. The most frequent contamination was detected as 4,4-DDE, followed by ethoprophos, quinalphos, methidation, paraoxon-methyl, phosalone and tetramethrin. The least common compounds were as follows: 2,4-DDD, endrin, HCH-alpha, fenamiphos sulfoxide, parathion ethyl, bitertanol, oxycarboxin, procymidone, fluazifop-butyl, trifluralin, bifenazate, DMF, fenpyroximate, PBDE-47, benzo(a)anthracene, benzo(b)fluoranthene, and benzo(g,h,i) perylene; of these only one was found in each bat. In terms of frequency and concentration, there was no significant difference between species and sex. An average of 26.1 pollutants was found in each bat. Thus, it was concluded that bats can be used as potential bioindicators in determining environmental pollution.

In vitro effects of erythromycin and florfenicol on primary cell lines of Unio crassus and Cyprinus carpio.

The ubiquitous use of antibiotics leads exposure of these chemicals on non-target aquatic species, while the toxicity assays for these chemicals are time/labor consuming and expensive. Alternative approaches using primary cell cultures which retain the tissue functionality at its highest form have received global attention compared to cell lines. In the current study, the cytotoxic effects of two commonly used antibiotics from amphenicol (florfenicol) and macrolide (erythromycin) groups were evaluated on primary cell cultures of Unio crassus (mantle, digestive gland, gill, and gonad) and Cyprinus carpio (gill and liver) using MTT and Neutral Red assays. The highest cytotoxic effects were found on the mussel digestive gland and carp liver cells for florfenicol and erythromycin, while the lowest cytotoxic effects were found in mussel mantle cells for both drugs in the MTT test. In the NR test, the highest cytotoxic effects of erythromycin and florfenicol were found in the mussel gill, mantle, gonad, and carp gill cells; the lowest cytotoxic effect of erythromycin was found in the mussel digestive gland, while the lowest effect of florfenicol was found in the carp liver cells. The cytotoxicity of florfenicol was quite low for the carp liver, while the cytotoxicity of erythromycin was quite low in the mussel digestive tract. Thus, it was concluded that cells made from mussel tissues could be used in ecotoxicity tests, and sensitivity may vary according to the tissue.

Companion animals get close to the toxic aspects of antropogenic world: cytotoxicity of phthalates and bisphenol A on dog testicular primary cells.

Phthalates, which are among the most abundant plasticizers, have detrimental effects on the reproductive system. Similar to human, dogs are prominently exposed to phthalates in daily routines at low concentrations; while toys, training devices and commercial dog foods are considered as the primary sources of exposure. This study aimed to reveal and compare the cytotoxic effects of selected phthalates (Benzyl butyl phthalate (BBP), Diethyl phthalate (DEP), Bis (2-ethylhexyl) phthalate (DEHP), Di-'isobutyl' phthalate (DIBP), Di-'isodecyl' phthalate (-DIDP) Di-'isononyl' phthalate (DINP), Dimethyl phthalate (DMP), Di-n-octyl phthalate (DNOP)), and Bisphenol A (BPA) following 24 h exposure on primary testicular parenchymal cells of dog in vitro at concentrations between 0.001 and 2.5 nM. According to cytotoxicity results, DEHP was found to be the most toxic phthalate with IC50 at 22.53 µM; while DMP was the least (169.17 nM). IC50 of BPA was 161.81 nM, less than the average (61.95 nM) of phthalates. In addition, dog primary testicular cells were found more susceptible to the high molecular weight phthalates (DNOP, DEHP, DINP, DIDP) than low molecular weight phthalates (DMP, DEP, DIBP, BBP). Further studies should focus on morphological, physiological and molecular differences to comprehend the mechanisms involved as well as decreasing the risk for impaired spermatogenesis caused by environmental toxicants in companion animal medicine.

Determination of the Polychlorinated Biphenyls Distribution in Different Fat Tissues of Cattle by Age and Gender.

Polychlorinated biphenyls (PCBs), which cause environmental pollution, are found in animal-based fatty foods. Due to their long half-life and lipophilic properties, they can accumulate in the fat tissues of cattle. The study was conducted to compare the PCB levels (PCB28, 52, 101, 118, 138, 153, and 180) in the different fat tissues (muscle, liver, kidney, spinal cord, lung, back fat, perihepatic fat, and perirenal fat) of cattle by age and gender. This information is also useful to evaluate the exposure risks for different bovine edible tissues. Therefore, 15 female and 15 male cattle under 24 months of age and 15 female and 15 male cattle over 24 months of age were used, and 480 samples were analyzed for target PCBs using gas chromatography-mass spectrometry. Of all the samples, two (50.2 µg/kg in perihepatic fat and 51.1 µg/kg in kidney) were found above the maximum residue limit; these samples were taken from the animals in the elderly female group (over 24 months). There were more PCBs in cattle older than 2 years. Muscle, kidney, and perihepatic fat presented higher PCB concentrations than other tissues, and perirenal fat presented lower PCB concentrations than other tissues. PCB101, PCB153, and PCB138 were found to have the highest contribution to the PCB concentration. Thus, it is concluded that perihepatic fat, muscle, or kidney should be sampled, particularly in routine residue monitoring, and specifically analyzed for PCB101, PCB153, and PCB138.

Piperlongumine inhibits cell growth and enhances TRAIL-induced apoptosis in prostate cancer cells

Objective: To investigate whether piperlongumine can sensitize prostate cancer cells to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and trigger apoptosis in prostate cells.Methods: Human prostate cancer cell lines PC3, LNCaP, and VCaP were cultured with piperlongumine and TRAIL. Then, cell proliferation, migration, caspase activation, apoptotic protein expressions, and death receptor expressions were measured. Results: Piperlongumine inhibited cell proliferation at low doses (<10 μM) alone and in combination with TRAIL (25 ng/mL), induced apoptosis, and suppressed cyclooxygenase activation. Additionally, piperlongumine induced expression of death receptors which potentiated TRAIL-induced apoptosis in cancer cells but did not affect decoy receptors. Piperlongumine also downregulated tumor cell-survival pathways, inhibited colony formation and migration of cancer cells alone or in combination with TRAIL. The combination of piperlongumine with TRAIL was found to be synergistic. Conclusions: Our findings indicate that piperlongumine can sensitize cancer cells to TRAIL through the upregulation of death receptors and can trigger apoptosis with the downregulation of anti-apoptotic proteins.

Effects of phthalates on bovine primary testicular culture and spermatozoa.

Among environmental endocrine-active chemicals, phthalates, commonly known as plasticizers, disrupt the development of the male reproductive tract. In this study, the effects of phthalates (DIBP, BBP, DINP, DBP, DEP, DEHP and DMP) were evaluated on cultures of bovine primary male reproductive cells (n = 3) and spermatozoa (n = 4). Epididymal (caput and corpus epididymis), testicular (parenchymal and mediastinal/tubular) and vas deferens cells (VDC) were prepared from samples collected from slaughterhouse. Second part of caput epididymis which have fewer amount of principal cells, were found to be less affected compared to the first part except DEHP; while corpus epididymis was found to be more affected with IC50 values below 0.976 ng/mL (except for DEP at 4.97 ng/mL). In testicular parenchymal cells, IC50 ranged from 0.15 to 4.11 ng/mL and for mediastinum from 0.01 to 7.31 ng/mL; where cytotoxic effects were more evident in mediastinal section. Least cytotoxic and even proliferational effects (DEHP, DMP and DEP) were observed in VDC, the muscular tube carrying sperm from epididymis to the ejaculatory duct. Least spermiotoxic phthalate was DBP (3.928 ng/mL); while DINP (0.550 ng/mL) induced highest cytotoxic effect on bovine spermatozoa. Differences in the cellular structure and/or the androgen receptor distribution effect the toxicity of phthalates. Our preliminary findings on bovine spermatozoa indicate possible morphological and motility alterations; which challenges further investigation of the transition of phthalates on semen straws used in cryopreservation. Increase of exposure to environmental contaminants raise the issue of the requirement of a new perspective on reproductive health, species and tissue specific differences should further be emphasized.

Selected persistent organic pollutants levels in the Ankara River by months.

Persistent organic pollutants (POPs) are banned in almost all countries due to their adverse health effects while they are still present in the environment due to their persistence. As the dissipation and the emission factors of POPs change by temperature and other environmental factors current study aimed to determine selected POPs, including polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and organochlorine pesticides (OCPs) in water and sediment samples collected from 12 stations located in Ankara River, Turkey, for 12 months. C-18 solid-phase extraction technique was used to extract organic pollutants and the analysis were performed using a validated gas chromatography-mass spectrometry method. DDE was the most frequently detected contaminant in water samples. Even though no PCB residues were present in water samples, PCB101 was the most common contaminant in sediment. Although both matrices had the least load of pollutants in winter, there was an increase in presence and concentration of pollutants from late spring to autumn.

Determination of selected endocrine disruptors in organic, free-range, and battery-produced hen eggs and risk assessment.

An increasing amount of evidence suggests that phthalic acid esters (PAE), polychlorinated biphenyls (PCB), polybrominated diphenyl ethers (PBDE), and organochlorine pesticides (OCP) are related to mutagenic, carcinogenic, and endocrine disruptor effects (EDCs). These lipophilic compounds are highly resistant to breakdown processes, and consequently remain in the environment, followed by uptake into the food chain. Human exposure to lipophilic compounds results from the consumption of food containing EDCs, mainly foodstuffs of animal origin with a high fat content, since these contaminants accumulate in fatty tissues. Foodstuffs in which EDCs can accumulate include meat, fish, eggs, and milk. We investigated the contamination in edible eggs to determine whether relative differences in the contaminants' residue levels appeared in three types of egg production (i.e., battery, free-range, and organic). The results showed that PAEs, especially dimethyl phthalate contamination, was the most abundant in the battery eggs, and the PCBs, PBDEs, and OCPs were the most abundant in the free-range eggs. The eggs were contaminated by more than one chemical, and as many as five contaminants (PCB180, PBDE47, dimethyl phthalate, diethyl phthalate, and di-n-butyl phthalate in battery eggs, and PCB138, PCB153, PCB180, diethyl phthalate, and di-2-ethylhexyl phthalate in organic eggs) were detected in the same egg. However, none of the chemicals detected were at the maximum limit of acceptable risk.

Herbal Bioenhancers in Veterinary Phytomedicine.

Herbal bioenhancers are active phytomolecules that increase the bioavailability, bioefficacy and biological activity of various drugs when coadministered at low concentrations. These valuable compounds reduce the dose, increase the treatment rate, decrease the treatment duration, drug resistance or related adverse reactions which have economical implications in livestock and pet medicine. Eventhough the concept of herbal bioenhancers are known for years through Ayurvedic medicine, the underlying mechanisms remains unclear. The main mechanisms involved are related to drug absorption (effect on solubility, drug efflux and transport proteins, increased permeability in gastrointestinal system) and drug metabolism (inhibition/induction of drug metabolysing enzymes, thermogenic effect). Due to species specific differences in these mechanisms, corresponding data on human and laboratory animal could not be attributed. As multidrug resistance is a major treat to both human and animal health, within "One Health" concept, efficient therapeutical strategies are encouraged by authorities, where focus on herbal supplements as a vast unexploited field remains to be researched within "Bioenhancement Concept." This review brings insight to mechanims involved in bioenhancing effect, examples of herbal extracts and phytoactive compounds and their potential in the veterinary medicine including different classes of drugs such as antibiotics, anticancerous, antiviral, and antituberculosis.

Antileukemic effects of piperlongumine and alpha lipoic acid combination on Jurkat, MEC1 and NB4 cells in vitro.

AIM OF STUDY: This research indicated to evaluate the effects of piperlongumine (PL), a biologically active alkaloid, and alpha lipoic acid (ALA), a naturally occurring cofactor existed in multienzyme complexes regulating metabolism on leukemia cells. Excessive production of reactive oxygen species (ROS) can lead to oxidative stress, a state that has been observed in several hematopoietic malignancies, including acute and chronic myeloid leukemias. The importance of the association between oxidative stress and malignancy is not currently clear; however, there is evidence that tumor.derived ROS may promote cell survival, migration and metastasis, proliferation and even drug.resistance depending on the origin of the cancer. Increased oxidative stress in leukemic cells may represent a potential therapeutic target, although there are differing opinions on whether therapeutic strategies should aim to antagonize or further promote oxidative stress in leukemic cells. MATERIALS AND METHODS: The effects of PL alone (5, 15, 30 µM) and in combination (30 µ M) with ALA (200 µ M) on Jurkat, NB4 and MEC1 leukemia cell lines were investigated through MTT, caspase-3 and cyclooxygenase-2 (COX-2) activities. RESULTS: Inhibition of COX-2 and the induction of caspase.3 cleavage in Nb4 (acute promyelocytic leukemia) cells were found to be significant following PL application and synergistic effects with combination of ALA (inhibition of COX-2 as 23.74% and 3.55-fold increase of caspase-3). CONCLUSION: PL and ALA may have a potential value as a therapeutic agent for patients with acute promyelocytic leukemia.

Measurement of selected polychlorinated biphenyls (PCBs) in water via ultrasound assisted emulsification-microextraction (USAEME) using low-density organic solvents.

Despite bans and restrictions for their adverse health effects including endocrine disruption, due to their stability in the environment, polychlorinated biphenyls (PCBs) are still of concern for their residues in several matrices. This study employed low-density ultrasound-assisted emulsification-microextraction (USAEME) to measure selected PCBs (28, 52, 101, 118, 138, 153, and 180) in water samples for gas chromatography-mass spectrometry analysis. Among tested solvents (isooctane, chloroform, hexane, and cyclohexane), 200 µL isooctane resulted in the highest yield for a 10 mL sample. The optimized method was validated and yielded recoveries of 87.29-92.83% with the limit of detection and limit of quantification (LOQ) values 3-12 ng/L and 10-40 ng/L, respectively. Twelve tap water samples collected in September 2014 were screened using this simple, rapid, and validated method. PCB concentrations in two samples were above the LOQ values; one sample contained 1,380 ng/L of PCB 118, 530 ng/L of PCB 138, and 152 ng/L of PCB 153, and the other contained 444 ng/L of PCB 138. Despite the city water supply being clean and the municipality employing all available measures to ensure clean water supply, the general public must be made aware of the regular maintenance of local water pipelines and storage tanks for the prevention of PCB contamination.

In Vitro Effects of Phthalate Mixtures on Colorectal Adenocarcinoma Cell Lines.

Among endocrine-disrupting chemicals, phthalates are an important concern because of their wide-spread exposure in humans and environmental contamination. Even though the use of some phthalates has been restricted for toys, some plastics, and food contact materials, exposure to the mixture of these contaminants at very low concentrations in various matrices are still being reported. In the current research, the effects of the mixture of some phthalates were studied. Di-n-butyl phthalate (DBP), n-butyl benzyl phthalate (BBP), di-2-ethylhexyl phthalate (DEHP), diisononyl phthalate (DiNP), di-n-octyl phthalate (DNOP), and diisodecyl phthalate (DiDP) were tested on two colorectal adenocarcinoma cell lines; DLD-1 and HT29 were studied as described before. Cells were treated with increasing log concentrations (0.33 ppt to 33.33 ppb) of the phthalate mixture; cell viability/proliferation was measured by MTT and staining with neutral red and crystal violet; lactate dehydrogenase (LDH) activity was measured following 24-h exposure. Cell viability/proliferation increased from phthalate treatment at concentrations less than 33.33 ppt. The phthalate mixture induced increases in HT29 proliferation of 10.94% at 33.33 ppt and 60.87% at 3.33 ppt, whereas this proliferation relation at lower concentrations was not found for DLD1 cells. The present study demonstrates preliminary information regarding the low dose induction of proliferation of the cancer cells by phthalate mixtures. Because non-monotonic dose responses are still being debated, further studies are required to re-evaluate the reference doses defined by governments for phthalates.