Single-Level Anterolateral and Posterior Interbody Fusion Techniques are Associated with Equivalent Long-Term Lumbar Reoperations.

STUDY DESIGN: Retrospective Cohort Study. OBJECTIVE: This study compares reoperation rates and complications following single-level ALIF/LLIF and TLIF/PLIF. SUMMARY OF BACKGROUND DATA: Anterior lumbar interbody fusion (ALIF), lateral lumbar interbody fusion (LLIF), transforaminal lumbar interbody fusion (TLIF), and posterior lumbar interbody fusion (PLIF) are widely used for degenerative disc disease. Lumbar interbody fusions have high rates of reoperation primarily related to adjacent segment pathology and pseudarthrosis. METHODS: The PearlDiver database was queried for patients (2010-2021) who had single-level ALIF/LLIF or TLIF/PLIF with same-day, single-level posterior instrumentation. ALIF/LLIF were combined and similarly, TLIF/PLIF were combined, given how these operations are indistinguishable with Current Procedural Terminology (CPT) coding. All patients were followed for ≥2 years and excluded if they had spinal traumas, fractures, infections, or neoplasms prior to surgery. The two cohorts, ALIF/LLIF and TLIF/PLIF, were matched 1:1 based on age, sex, Elixhauser-Comorbidity Index (ECI), smoking status, and diabetes. The primary outcome was the incidence of all-cause subsequent lumbar operations. Secondary outcomes included 90-day surgical complications. RESULTS: After 1:1 matching, each cohort contained 14,070 patients. All-cause subsequent lumbar operations were nearly identical at 5-year follow-up (9.4% ALIF/LLIF vs. 9.5% TLIF/PLIF, P=0.91) (Table 2). Survival analysis using all-cause subsequent lumbar operations as the endpoint showed an equivalent 10-year survival rate of 86.0% (95%CI: 85.2-86.8) (Figure 1). Within 90 days, TLIF/PLIF had more infections (1.3% vs. 1.7%, P=0.007) and dural injuries (0.2% vs. 0.4%, P=0.001). There was no difference in wound dehiscence, hardware complications, or medical complications (Table 3). CONCLUSION: As utilized in real-world clinical practice, single-level anterolateral versus posterior approaches for interbody fusion have no effect on long term reoperation rates.

Probabilistic ecological risk assessment of heavy metals using the sensitivity of resident organisms in four Korean rivers.

The environment has been continuously exposed to heavy metals by various routes, from both natural and artificial sources. In particular, heavy metals in water can affect aquatic organisms adversely, even at very low concentrations, and can lead to the disturbance of the ecosystem balance and biodiversity. Ecological risk assessments are conducted to protect the environment from such situations, primarily by deriving the predicted no-effect concentration (PNEC) from the species sensitivity distribution (SSD). This study developed the SSDs based on the species living in Korean freshwater for four heavy metals including cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn). The species compositions of the SSDs were examined, and three types of PNECs were derived by applying different assessment factors (AF). In addition, the occurrence and concentrations of heavy metals in Korean rivers were investigated, and the ecological risk assessment was carried out to compare the SSDs with the environmental concentrations. The SSDs were developed using a sufficient number of species, but the missing data of plants and insects provided an incomplete species composition. The results show that Cd and Pb in the environmental concentrations of rivers would not cause any risk to aquatic organisms from the derived PNEC. However, some organisms might be adversely affected by the concentrations of Zn, and a small amount of risk was expected under the conservative PNEC. The distribution of Cu in the rivers was not considered to be safe for aquatic organisms because the average environmental concentrations potentially affected the proportion of the SSD, and the environmental concentrations exceeded the PNECs. The concentrations of Cu and Zn in industrial waters indicated a considerable risk to aquatic organisms, and the probability of exceeding the PNECs appeared to be quite high. Therefore, this study indicates that additional actions and parallel field studies are required based on the risk posed to aquatic organisms by Cu and Zn in four Korean rivers.

Combined toxic effect of airborne heavy metals on human lung cell line A549.

Many studies have demonstrated that heavy metals existing as a mixture in the atmospheric environment cause adverse effects on human health and are important key factors of cytotoxicity; however, little investigation has been conducted on a toxicological study of a metal mixture from atmospheric fine particulate matter. The objective of this study was to predict the combined effects of heavy metals in aerosol by using in vitro human cells and obtain a suitable mixture toxicity model. Arsenic, nickel, and lead were selected for mixtures exposed to A549 human lung cancer cells. Cell proliferation (WST-1), glutathione (GSH), and interleukin (IL)-8 inhibition were observed and applied to the prediction models of mixture toxicity, concentration addition (CA) and independent action (IA). The total mixture concentrations were set by an IC10-fixed ratio of individual toxicity to be more realistic for mortality and enzyme inhibition tests. The results showed that the IA model was statistically closer to the observed results than the CA model in mortality, indicating dissimilar modes of action. For the GSH inhibition, the results predicted by the IA and CA models were highly overestimated relative to mortality. Meanwhile, the IL-8 results were stable with no significant change in immune reaction related to inflammation. In conclusion, the IA model is a rapid prediction model in heavy metals mixtures; mortality, as a total outcome of cell response, is a good tool for demonstrating the combined toxicity rather than other biochemical responses.

Prevalence of cervical myelomalacia in adult patients requiring a cervical magnetic resonance imaging.

STUDY DESIGN: A retrospective study. OBJECTIVE: To determine the prevalence of cervical myelomalacia in patients requiring cervical magnetic resonance imaging. SUMMARY OF BACKGROUND DATA: The presence of myelomalacia in the cervical spinal cord in has prognostic value after decompression surgery. Some surgeons consider operative treatment of all patients with myelomalacia based on the assumption that myelomalacia is a relatively uncommon finding. However, the prevalence of cervical myelomalacia in symptomatic patients has not been fully established. METHODS: The sentences containing the key word "myelomalacia" were extracted from a large database of cervical magnetic resonance imaging reports and manually reviewed by an experienced neuroradiologist to determine whether the interpreting radiologists thought there was myelomalacia in the cervical spinal cord. The prevalence of myelomalacia was calculated for different age and sex groups, as well as for the medical specialties/subspecialties of the referring providers. RESULTS: A total of 964 of 23,139 patients who underwent magnetic resonance imaging findings consistent with cervical myelomalacia. The overall prevalence of myelomalacia in this population was 4.2%; 5.6% in males and 3.0% in females. The rates increased linearly with age until the eighth decade when it reached 7.6% overall, 9.2% for males and 6.2% for females, but dropped to 5.1% for patients older than 80. There were considerable variations in the prevalence of myelomalacia in patients referred by different specialties/subspecialties. Specialists in spinal cord injury had the highest rate (28.7%), followed by neurological (8.4%) and orthopedic (6.4%) spine surgeons, general neurosurgeons (5.5%), and neurologists (4.2%). Specialists who generally do not treat patients with spine problems had the lowest (1.2%) followed by nonspine orthopedists (1.6%) and primary care doctors (2.1%). CONCLUSION: The overall prevalence of cervical myelomalacia was relatively low in the studied population, and it was affected by age, sex, and the specialties/subspecialties of referring providers. These results may help direct treatment guidelines and allow for informed discussions with patients in terms of the risk versus the benefit of surgery. LEVEL OF EVIDENCE: 1.

Acute and chronic response of Daphnia magna exposed to TiO2 nanoparticles in agitation system.

Aquatic toxicity of titanium dioxide nanoparticles (TiO2 NPs) to Daphnia magna was characterized using a completely stirred bioassay system intended to keep particles in suspension thereby maintaining a consistent exposure. The 48-h LC50 was 4.5 mg/L TiO2 NPs, whereas LC50 values for 7 and 14-days exposures were 2.7 and 1.9 mg/L, respectively. An exposure of 1.5 mg/L over a 21-days exposure resulted in significant reductions in fecundity. While reproduction was initially reduced in the 0.5 and 1.0 mg/L exposures, it recovered and was similar to the control by 21 days. For reproduction inhibition, NOEC was 1.0 mg/L. Exposure to 2.5 mg/L TiO2 NPs resulted in 40 % of the organisms failing to become gravid; all surviving organisms exposed to 5.0 mg/L failed to become gravid. The increased sensitivity was due to the refinement in the bioassay system that kept NP in suspension resulting in consistent exposure concentrations.

Prior abdominal surgery is associated with an increased risk of postoperative complications after anterior lumbar interbody fusion.

STUDY DESIGN: Retrospective medical record review. OBJECTIVE: The purpose of this study was to determine whether a history of abdominal/pelvic surgery confers an increased risk of retroperitoneal anterior approach-related complications when undergoing anterior lumbar interbody fusion. SUMMARY OF BACKGROUND DATA: As anterior lumbar interbody fusion gains popularity, both anterior retroperitoneal approach have become increasingly used. METHODS: The records of 263 patients, who underwent infraumbilical retroperitoneal approach to the anterior aspect of the lower lumbar spine for a degenerative spine condition between 2007 and 2011 were retrospectively reviewed. Patient's demographics, risk factors, preoperative diagnosis, surgical history, level of the anterior fusion, and perioperative complications were collected. Anterior retroperitoneal approach to the spine was carried out by a single general surgeon. RESULTS: Ninety-seven patients (37%) developed at least 1 complication. Forty-nine percent of patients with a history of abdominal surgery developed a postoperative complication compared with 28% of patients without such history (RR = 1.747, P≤ 0.001). After controlling for other factors such as age, sex, body mass index, diagnostic groups, and preoperative comorbidities (hypertension, diabetes, and smoking status), these differences remained statistically significant. When each type of complication was considered separately, there was a statistically significant difference in the incidence of general complications (RR = 2.384, P = 0.007), instrumentation-related complications (RR = 2.954, P = 0.010), and complications related to the anterior approach (RR = 1.797, P = 0.021). CONCLUSION: Anterior lumbar interbody fusion via a midline incision and a retroperitoneal approach was associated with 37% overall rate of complication. Patients with a history of abdominal or pelvic surgery are at a higher risk of developing general, instrumentation, and anterior approach-related complications.

Bioconcentration and distribution of silver nanoparticles in Japanese medaka (Oryzias latipes).

The study of the bioconcentration of silver nanoparticles (AgNPs) is important to fully understand their hazard potential in the aquatic environment. We synthesized AgNPs radiolabeled with silver isotopes ((110m)Ag) to quantify the bioconcentration of AgNPs coated with citrate (AgNPs-CIT) and polyvinylpyrrolidone (AgNPs-PVP) in Japanese medaka, and to investigate the biodistribution of silver in organs, which were compared with (110m)AgNO3. BCF values were determined to be 39.8±7.4, 42.5±5.1 and 116.4±6.1Lkg(-1) for AgNPs-CIT, AgNPs-PVP and AgNO3, respectively. The release of more silver ions in AgNPs-PVP contributed to a different kinetic uptake pattern with AgNPs-CIT, which was similar to that of AgNO3. Bioconcentrated AgNPs in medaka were not observed to be eliminated, independent of surface coating differences, similarly to AgNO3. There was no difference in biodistribution in each organ before and after depuration in two types of AgNPs and AgNO3, all of which were mainly concentrated in the liver. This study quantified the bioconcentration and distribution of AgNPs and AgNO3 more precisely by utilizing a silver isotope, which is helpful in monitoring the toxicity of AgNPs to Japanese medaka.

Reduction of toxicity of antimicrobial compounds by degradation processes using activated sludge, gamma radiation, and UV.

The occurrence and persistence of pharmacologically active compounds in the environment has been an increasingly important issue. The objectives of this study were to investigate the decomposition of aqueous antimicrobial compounds using activated sludge, γ-irradiation, and UV treatment, and to evaluate the toxicity towards green algae, Pseudokirchneriella subcapitata, before and after treatment. Tetracycline (TCN), lincomycin (LMC) and sulfamethazine (SMZ) were used as target compounds. Gamma (γ)-irradiation showed the highest removal efficiency for all target compounds, while UV and activated sludge treatment showed compound-dependent removal efficiencies. TCN and SMZ were well degraded by all three treatment methods. However, LMC showed extremely low removal efficiency for UV and activated sludge treatments. Overall, the algal toxicity after degradation processes was significantly decreased, and was closely correlated to removal efficiency. However, in the case of γ-irradiated TCN, UV and activated sludge treated LMC as well as sludge treated SMZ, the observed toxicity was higher than expected, which indicates the substantial generation of byproducts or transformed compounds of a greater toxicity in the treated sample. Consequently, γ-radiation treatment could be an effective method for removal of recalcitrant compounds such as antibiotics.

The convergence of medicine and neurotoxins: a focus on botulinum toxin type A and its application in aesthetic medicine--a global, evidence-based botulinum toxin consensus education initiative: part I: botulinum toxin in clinical and cosmetic practice.

BACKGROUND: The U.S. Food and Drug Administration has approved four distinct formulations of botulinum toxin (BoNT) serotypes A and B (BoNTA and BoNTB) for medical use. These four products are indicated for many medical applications, but the three BoNTA formulations are the most widely used worldwide and are the only products approved for aesthetic use. The latest approval of a BoNTA with no complexing proteins (incobotulinumtoxinA) necessitates a review and discussion of differences between available formulations and the effect that these differences may have on clinical practice. OBJECTIVES: To review the history, science, safety information, and current and emerging applications of BoNT in clinical and cosmetic practice and to compare commercially available BoNTA formulations. METHODS AND MATERIALS: Publications, clinical trials, and author experience were used as a basis for an up-to-date review of BoNT and its use in human medicine. The similarities and differences between formulations are presented, and diffusion, spread, equivalency ratios, stability, and storage are discussed. RESULTS: Each commercial formulation has unique characteristics that may influence its use in aesthetic medicine. Familiarity with the similarities and differences between products will aid physicians in making patient care decisions. CONCLUSION: New formulations, emerging uses, and continued research into the science and uses of BoNTA will lead to increasingly refined therapeutic approaches and applications. Continued education is important for physicians to optimize use of the agent according to the most current evidence and approaches.

Developmental toxicity of Japanese medaka embryos by silver nanoparticles and released ions in the presence of humic acid.

The final destination point of nanoparticles is the environment, where they remain a long period; therefore, a deep understanding of the relationship between nanoparticles and the environmental factors is required. Japanese medaka embryos were exposed to two differently prepared AgNPs: freshly prepared AgNPs and aged AgNPs. With these two AgNP preparations, we studied the impacts of humic acid in terms of embryonic toxicity, as well as the behavior of AgNPs. Aged AgNPs exhibited a lower lethal concentration (LC50) value (1.44mg/L) compared to fresh AgNPs (3.53mg/L) through 96h acute toxicity tests, due to the release of silver ions, as confirmed by kinetic analysis. The presence of humic acids considerably reduced the toxicity of aged AgNPs due to complexation with silver ions. Agglomeration, induced by interactions with humic acid, might reduce the bioavailability of AgNPs to Japanese medaka embryos. This study demonstrates that aged AgNPs releasing more silver ions are more toxic than fresh AgNPs, and humic acids play a role in reducing the toxicity of aged AgNPs.

Influence of 17ß-estradiol binding by dissolved organic matter isolated from wastewater effluent on estrogenic activity.

The aims of this study were to determine the sorption coefficient (LogK(DOC)) of 17ß-estradiol (E2), according to the size and composition of dissolved organic matter (DOM) isolated from wastewater effluent using a fluorescence quenching (FQ) method, and to measure the estrogenic changes due to the extent of E2 sorption onto effluent DOM (EfOM) by using an E-screen bioassay. The highest logK(DOC) of E2 for a DOM size fraction less than 0.2 µm was observed by 4.87 ± 1.87 Lkg(-1)(DOC), and its estrogenicity was the lowest among all the size fractions at 1.2 ng-EEQL⁻¹. However, E2 estrogenicity for a DOM size fraction less than 5 kDa was as high as that for the positive control due to the absence of fulvic acid- and protein-like DOM to bind with E2. The estrogenic activity for the hydrophobic fraction bound with E2 was significantly reduced to 1.6 ng-EEQL⁻¹, while that for the hydrophilic fraction having no binding with E2 was 2.6 ng-EEQL⁻¹, which was similar to that of the positive control (i.e., 2.8 ng-EEQL⁻¹). The results support a conclusion that the change in estrogenicity was due to the strong sorption affinity of E2 onto DOM.

Acute toxicity of a mixture of copper and single-walled carbon nanotubes to Daphnia magna.

Nanomaterials released into the environment will interact with many materials including other contaminants. This may influence bioavailability and fate of both the nanoparticles and the other contaminants. The present study examined the effect of a combination of soluble copper and surface-modified single-walled carbon nanotubes (SWNTs) on Daphnia magna. Lysophosphatidylcholine (LPC) was used to modify the surface of SWNTs, reducing the surface hydrophobicity of the tubes and thereby producing a stable aqueous nanoparticle suspension. The toxicity of the nanoparticle-copper (Cu) mixture was determined to be additive. The addition of nontoxic concentration of LPC-SWNTs enhanced the uptake and toxicity of copper. Greater amounts of Cu were shown to accumulate in D. magna upon addition of 0.5 and 1.0 mg/L LPC-SWNTs.

Bioconcentration of perfluorinated compounds in blackrock fish, Sebastes schlegeli, at different salinity levels.

Bioconcentration of perfluorinated compounds (PFCs) was studied in a biphasic (uptake and elimination) study with blackrock fish, Sebastes schlegeli. The blackrock fish was acclimated to varying salinities over a two-week period before the present study. Among the four selected PFCs: perfluorooctane sulfonate (PFOS), perfluoro-octanoic acid (PFOA), perfluorodecanoic acid (PFDA), and perfluoroundecanoic acid (PFUnDA), PFUnDA accumulated significantly in serum, followed by PFDA, PFOS, and PFOA, in that order, while the accumulation profile in liver was PFOS > PFUnDA > PFDA > PFOA. Total PFC levels in plasma were approximately four times greater than those found in liver. The uptake and elimination rate constants (K(u) and K(e)) of PFCs decreased as salinity decreased, suggesting delayed diffusion of PFCs between water and fish, possibly associated with the osmolality gradient. A significant correlation was found between bioconcentration factors (BCF) of PFCs and salinity, except for PFOA, possibly resulting from the effects of salinity on biological responses and chemical activity of PFCs. Even though salinity did not affect the kinetics of PFC accumulation in serum and liver, the results provide useful information on the toxicokinetics of PFCs for saltwater fish.

Oxidative stress responses of Daphnia magna exposed to TiO(2) nanoparticles according to size fraction.

Size is one of important factors determining titanium dioxide nanoparticle (TiO(2) NP) toxicity since penetration is eased with decreasing particle size and bioavailability is increased. The effect of particle size on oxidative stress against titanium dioxide nanoparticle (TiO(2) NP) exposure to Daphnia magna was investigated with both acute and chronic toxicity tests. Experiments on biochemical responses, repeatedly performed after size fractionation of the NPs using filtration, focused on the activities of four antioxidant enzymes: catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPX), and glutathione-S-transferase (GST). In the chronic bioassay, the mortality was significantly increased at TiO(2) NP concentrations of 5 and 10mg/L; however, no reduction of the reproduction ability was observed. Biochemical measurements showed that TiO(2) NP exposure significantly increased the antioxidant enzyme activities in D. magna. CAT, GPX and GST, but not SOD, showed a concentration-dependent increase. In terms of size fraction, particles ranging from 400 to 800nm exhibited an increase of antioxidant enzyme activities in GST and GPX. These biochemical level observations suggested that TiO(2) NP toxicity was mediated by reactive oxygen species (ROS) generation via oxidative stress in D. magna. The increased mortality at the concentration of 5mg/L in the chronic bioassay was attributed to accumulated TiO(2) NPs in the intestine of D. magna, which might induce effects such as oxidative stress relating to the induction of antioxidant enzymes.

Sorption of estrogens onto different fractions of sediment and its effect on vitellogenin expression in male Japanese medaka.

This study investigated the sorption capacity of estrogenic compounds-such as estrone (E1), 17beta-estradiol (E2), and 17alpha-ethynylestradiol (EE2)-of different sediment particle fractions. Two-sized fractions of sediment were used in the experiments, with a particle size <1 microm (mostly from 450 to 800 nm) and >1 microm up to 50 microm. Sorption kinetics were followed using a two-step reaction in which the major amount of chemicals was sorbed rapidly within minutes and then gradually increased until equilibrium was reached after 48 h. The sorption capacity of the fine particle fraction (particle size <1 microm) was shown to be significantly higher than that of the large fraction (1 microm < particle size < 50 microm). The sorption kinetics and isotherm were adequately predicted by using a pseudo second-order model and the Freundlich equation, respectively. Total organic carbon (TOC) content and surface area of particle fractions were also measured. Although the effects of TOC on the sorption of estrogens could not be verified, a higher surface area of fine particle fractions may significantly increase sorption capacity to target compounds. Sorption of estrogens onto sediment particles could be used to explain the differences of estrogenic activity of E2 spiked into different size fractions of particle suspensions.

Estrogenic chemicals and estrogenicity in river waters of South Korea and seven Asian countries.

The effects of treatment processes on estrogenicity were evaluated by examining estradiol equivalent (EEQ) concentrations in influents and effluents of sewage treatment plants (STPs) located along Yeongsan and Seomjin rivers in Korea. The occurrence and distribution of estrogenic chemicals were also estimated for surface water in Korea and compared with seven other Asian countries including Laos, Cambodia, Vietnam, China, Indonesia, Thailand and Malaysia. Target compounds were nonylphenol (NP), octylphenol (OP), bisphenol A (BPA), estrone (E1), 17beta-estradiol (E2), 17alpha-ethynylestradiol (EE2) and genistein (Gen). Water samples were pretreated and analyzed by liquid-liquid extraction (LLE) and gas chromatography/mass spectrometry (GC/MS). The results showed that the treatment processes of Korean STPs were sufficient to reduce the estrogenic activity of municipal wastewater. The concentrations of phenolic xenoestrogens (i.e., NP, OP and BPA) in samples of Yeongsan and Seomjin rivers were smaller than those reported by previous studies in Korea. In most samples taken from the seven Asian countries, the presence of E2 and EE2 was a major contributor toward estrogenic activity. The EEQ concentrations in surface water samples of the seven Asian countries were at a higher level in comparison to that reported in European countries, America and Japan. However, further studies with more sampling frequencies and sampling areas should be carried out for better evaluation of the occurrence and distribution of estrogenic compounds in these Asian countries.

Influence of multiwalled carbon nanotubes dispersed in natural organic matter on speciation and bioavailability of copper.

The dispersion of multiwalled carbon nanotubes (MWNTs) by natural organic matter (NOM) may influence the bioavailability of MWNTs and other contaminants. The speciation and bioavailability of copper (Cu) in MWNTs-associated NOM was studied using Daphnia magna. Cu titration data indicated that the binding affinity of Cu for MWNTs-associated NOM was lower than that for NOM alone. The free Cu(2+) ion activity was increased even by the addition of a low nontoxic concentration of 1.0 mg/L MWNTs. The 96 h LC(50) of MWNTs was determined to be 2.48 mg/L. The Fourier transform infrared (FTIR) spectra results showed clearly different features in Cu spiked between NOM and MWNTs-associated NOM, indicating that the interruption of Cu binding was probably due to steric stabilization of the MWNTs dispersed in NOM, which inhibited the complexation by rendering the functional groups in NOM less favorable to Cu. The mortality and biochemical reactive oxygen species (ROS) production in the D. magna bioassay were enhanced in MWNTs-associated NOM compared to NOM alone because of increased free Cu(2+) ion activity as expected from the titration and FTIR results. This study suggests the bioavailability of Cu is enhanced by the presence of MWNTs interacting with NOM.

Eya4 regulation of Na+/K+-ATPase is required for sensory system development in zebrafish.

To investigate the mechanisms by which mutations in the human transcriptional co-activator EYA4 gene cause sensorineural hearing loss that can occur in association with dilated cardiomyopathy, we studied eya4 expression during zebrafish development and characterized eya4 deficiency. eya4 morphant fish embryos had reduced numbers of hair cells in the otic vesicle and lateral line neuromasts with impaired sensory responses. Analyses of candidate genes that are known to be expressed in a temporal and spatial pattern comparable to eya4 focused our analyses on atp1b2b, which encodes the beta2b subunit of the zebrafish Na+/K+-ATPase. We demonstrate atp1b2b levels are reduced in eya4 morphant fish and that morpholino oligonucleotides targeting the atp1b2b gene recapitulated the eya4 deficiency phenotypes, including heart failure, decreased sensory hair cell numbers in the otic vesicle and neuromasts, and abnormal sensory responses. Furthermore, atp1b2b overexpression rescued these phenotypes in eya4 morphant fish. We conclude that eya4 regulation of Na+/K+-ATPase is crucial for the development of mechanosensory cells and the maintenance of cardiac function in zebrafish.

Comparison of the removal efficiency of endocrine disrupting compounds in pilot scale sewage treatment processes.

The removal efficiency of endocrine disrupting compounds from effluents using pilot scale sewage treatment processes, including various treatment technologies, such as membrane bioreactors (MBR), nanofiltration (NF) and reverse osmosis (RO) for the purpose of water reuse, were estimated and compared. The calculated estrogenic activity, expressed in ng-EEQ/l, based on the concentration detected by GC/MS, and relative potencies for each target compound were compared to those measured using the E-screen assay. The removal efficiencies for nonylphenol, was within the range of 55-83% in effluents. High removal efficiencies of approximately >70% based on the detection limits were obtained for bisphenol A, E1, EE2 and genistein with each treatment processes, with the exception of E1 ( approximately 64%) using the MBR process. The measured EEQ values for the effluents from the MBR, NF and RO processes also indicated low estrogenic activities of 0.65, 0.23 and 0.05 ng-EEQ/l, respectively. These were markedly reduced values compared with the value of 1.2 ng-EEQ/l in influent. Consequently, the removals of EDCs in terms of the EEQ value from the biological and chemical determinations were sufficiently achieved by the treatment process applied in this study, especially in the cases of the NF and RO treatments.

Occurrence and removal of pharmaceuticals and endocrine disruptors in South Korean surface, drinking, and waste waters.

Liquid chromatography/tandem mass spectrometry (LC-MS/MS) with electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) was used to measure the concentrations of 14 pharmaceuticals, 6 hormones, 2 antibiotics, 3 personal care products (PCPs), and 1 flame retardant in surface waters and wastewater treatment plant effluents in South Korea. Tris (2-chloroethyl) phosphate (TCEP), iopromide, naproxen, carbamazepine, and caffeine were quite frequently observed (>80%) in both surface waters and effluents. The analytes of greatest concentration were iopromide, TCEP, sulfamethoxazole, and carbamazepine. However, the primary estrogen hormones, 17alpha-ethynylestradiol and 17beta-estradiol, were rarely detected, while estrone was detected in both surface water and wastewater effluent. The elimination of these chemicals during drinking water and wastewater treatment processes at full- and pilot-scale also was investigated. Conventional drinking water treatment methods were relatively inefficient for contaminant removal, while efficient removal (approximately equal to 99%) was achieved by granular activated carbon (GAC). In wastewater treatment processes, membrane bioreactors (MBR) showed limited target compound removal, but were effective at eliminating hormones and some pharmaceuticals (e.g., acetaminophen, ibuprofen, and caffeine). Membrane filtration processes using reverse osmosis (RO) and nanofiltration (NF) showed excellent removal (>95%) for all target analytes.