Validation of a gas chromatography-triple quadrupole mass spectrometry method for confirmatory analysis of dioxins and dioxin-like polychlorobiphenyls in feed following new EU Regulation 709/2014

The European Regulations laying down methods of sampling and analysis for the EU official control of levels of polychlorodibenzo-p-dioxins (PCDDs), polychloro-dibenzofurans (PCDFs), dioxin-like (DL) and non dioxin-like (NDL) PCBs in food and feed have been recently amended by EU Regulation Nos. 589/2014 and 709/2014. A major update is the recognition of gas chromatography (GC) triple quadrupole mass spectrometry (GC-QQQMS/MS) as a confirmatory tool for checking compliance with maximum levels (ML). These revisions have been initiated since this technology now exhibits similar performances to GC (magnetic sector) high resolution mass spectrometry (GC-HRMS). In this paper, we show a fully validated method for PCDD/Fs and DL-PCBs analysis in feed material of plant origin (vegetable oil) using GC-QQQMS/MS following the dedicated EU Regulation 709/2014. We show that individual analytical criteria (selectivity, linearity, quant/qual MRM transitions, accuracy around ML of 1.50ng WHO2005TEQ/kg, within-lab reproducibility, robustness, and background subtraction) meet the strict requirements set by the EU Regulation. We also propose a clear interpretation of instrumental limit of quantitation (iLOQ) as a 'performance-LOQ', defined in a specific way for GC-QQQMS/MS, and method limit of quantitation (mLOQ) as 'real-LOQ' that is used to report bound results. Eventually, the evaluation of measurement uncertainty, following a top-down approach and data produced with our method, demonstrates similar results than with GC-HRMS, thus offering a reliable alternative to the standard method for vegetable oil.

Dioxin levels in fertilizers from Belgium: determination and evaluation of the potential impact on soil contamination

Dioxins are harmful persistent organic pollutants (POPs) to which humans are exposed mostly via the consumption of animal products. They can enter the food chain at any stage, including crop fertilization. Fertilizers belong to several categories: synthetic chemicals providing the essential elements (mostly N, P and K) that are required by the crops but also organic fertilizers or amendments, liming materials, etc. Ninety-seven samples of fertilizers were taken in Belgium during the year 2011 and analyzed after a soft extraction procedure for polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (DL-PCBs) using GC-IDHRMS. Only small qualitative differences could be observed between the main fertilizer categories since the PCDD:PCDF:DL-PCB average ratio obtained with the results expressed in TEQ was often close to 30:30:40 (typically for sewage sludge) or 40:30:30 (typically for compost). The median dioxin levels determined were generally lower than recorded previously and were the highest for sewage sludge and compost (5.6 and 5.5 ng TEQ/kg dry weight (dw), respectively). The levels in other fertilizers were lower including manure for which the median value was only 0.2 ng TEQ/kg dw. Several fertilization scenarios relying on the use of those fertilizers were assessed taking into consideration the application conditions prevailing in Belgium. From this assessment it could be concluded that the contribution of fertilizers to the overall soil contamination will be low by comparison of other sources of contamination such as atmospheric depositions. At the field scale, intensive use of compost and sewage sludge will increase dramatically the dioxin inputs compared with other fertilization practices but this kind of emission to the soil will still be relatively low compared to the dioxin atmospheric depositions.

Risk assessment of Belgian adults for furan contamination through the food chain

Risk assessment is an interdisciplinary process used to quantify the risk linked to a hazard. In the present paper it is applied to quantify the risk linked to furan ingestion through the food chain for the Belgian adult population. Two approaches, deterministic and probabilistic, were carried out in parallel. The deterministic method relied on a case study, whereas the probabilistic approach involved statistical distributions of contamination and consumption data to calculate a statistical distribution of the daily intake. First, the deterministic method revealed a low estimated daily intake (EDI) for the average population (380 ng*(kg(bw)*day)⁻¹) and a huge contribution of coffee consumption to the EDI (55%). Increasing or decreasing the daily coffee consumption by one cup can affect the EDI by about 22%. Afterwards, the probabilistic approach showed that the average population has a low EDI (494 ng*(kg(bw)*day)⁻¹), and that high contamination levels were only registered in a small proportion of the population. Finally, a comparison of the RfD(chronic oral) showed that less than 10% of the Belgian population had an EDI above the reference dose proposed by the USEPA; the majority of the population had an EDI 20% below the reference dose. The margin of exposure (MoE) approach indicated that the level of risk related to furan intake through ingestion is low, with a MoE > 10,000 for more than 10% of the population and no result < 100.

Evaluation of a pen device for self-administration of recombinant human FSH in clomiphene citrate-resistant anovulatory women undergoing ovulation induction

This open-label multicentre study evaluated ease of use, safety, and efficacy of a pen device for self-administration of recombinant follicle-stimulating hormone (rFSH) in 43 subjects undergoing ovulation induction. Follitropin beta was administered subcutaneously with the Follistim Pen within 3 days of onset of menses. A 75 IU starting dose could be increased by 25 or 50 IU on days 8 and 15 if no ovarian response was observed. Human chorionic gonadotrophin (HCG; 10,000 IU) was administered when one follicle > or =18 mm or two to three follicles > or =15 mm were observed. Subjects received standardized instruction for the pen device and subject comprehension was recorded as subjects practised and prepared injections. Ease of use was also evaluated by questionnaire. Forty-four subjects enrolled; 43 were treated with rFSH and 41 were treated with HCG. The comprehension questionnaire revealed that during the mock injection, 100% of subjects properly loaded the cartridge into the pen device, while 95% selected the correct dose and 100% self-injected the medication prescribed. During the second actual injection, 100% of subjects comprehended these pen-related steps. The ease-of-use questionnaire showed that 100% of the subjects rated the overall experience of self-administering with the pen as 'very good' to 'good'. Mean duration and total amount of follitropin beta were 11.4 +/- 4.2 days and 1070.3 +/- 580.3 IU respectively. Ovulation rate was 95%. Biochemical and ongoing pregnancy rates per attempt were 34.9 and 30.2% respectively. Three subjects experienced serious adverse events [asthma; ovarian hyperstimulation syndrome (OHSS) and pain; OHSS]. In conclusion, the pen device provides an easy, safe, and effective way for women to self-administer follitropin beta during ovarian stimulation.

Is chemiluminescent immunoassay an appropriate substitution for radioimmunoassay in monitoring estradiol levels?

OBJECTIVE

To determine the correlation between serum estradiol measurements by chemiluminescent immunoassay (CIA) vs. radioimmunoassay (RIA) in two groups: patients treated with gonadotropins and patients treated with oral estrogen.

DESIGN

Prospective study.

SETTING

Assisted Reproductive Technology (ART) program based in a university-affiliated hospital in Manhasset, New York.

PATIENT(S)

Three hundred forty-eight patients undergoing gonadotropin stimulation and 63 patients receiving oral estrogen between July and December, 1997.

INTERVENTION(S)

Estradiol levels were measured concomitantly on all patients undergoing gonadotropin stimulation for IVF and all patients receiving oral estrogen for a frozen-thaw cycle.

MAIN OUTCOME MEASURE(S)

RIA:CIA ratio.

RESULT(S)

In the group undergoing gonadotropin stimulation, the median RIA:CIA ratio was 0.92, RIA = 1.26 x CIA(0.96), r = 0.98. In the group receiving oral estrogen, the median ratio was 3.93, RIA = 2.9 x CIA(1.05), r = 0.89.

CONCLUSION(S)

Estradiol levels determined by CIA correlate closely with RIA results for patients being treated with gonadotropins. Conversely, for patients receiving oral estrogen, CIA levels are one-third or less of the RIA level.

Novel concepts for GaAs/LiNbO(3) layered systems and their device applications

Thin semiconductor quantum well structures fused onto LiNbO(3 ) substrates using the epitaxial lift-off (ELO) technology offer the possibility of controlling the surface acoustic wave (SAW) velocity via field effect. The tunability of the conductivity in the InGaAs quantum well results in a great change in SAW velocity, in general, accompanied by an attenuation. We show that an additional lateral modulation of the sheet conductivity reduces the SAW attenuation significantly, enhancing device performance. At high SAW intensity the bunching of electrons in the SAW potential also leads to a strong reduction of attenuation. These effects open new possibilities for voltage-controlled SAW devices. We demonstrate a novel, wireless, passive voltage sensor, which can be read out from a remote location.

Theory and application of passive SAW radio transponders as sensors

Surface acoustic wave (SAW) radio transponders make it possible to read identification codes or measurement values from a remote location. The decisive advantage of these SAW transponders lies in their passive operation (i.e., no power-supply), and in the possibility of wireless installation at particularly inaccessible locations. The passive SAW transponders are maintenance free. Identification marks respond to an interrogation signal with their nonchanging identification pattern. In wireless SAW sensors the physical or chemical properties to be detected change the propagation characteristics of the SAW. SAW radio transponders are advantageously placed on moving or rotating parts and in hazardous environments such as contaminated or high voltage areas. They also can be used for contactless measurements in high vacuum process chambers, under concrete, extreme heat, or strong radioactive radiation, where the use of conventional sensors is complicated, dangerous, or expensive. In this paper we discuss the principles of wireless passive SAW transponders and present a radio frequency interrogation unit and several passive radio SAW sensors developed for noncontact measurements of temperatures, pressures, torques, and currents.

The value of routine screening of female serum for antisperm antibodies in assisted reproductive technology cycles

OBJECTIVE

To determine the effect of antisperm antibodies in the female serum on fertilization and pregnancy rates (PRs) in assisted reproductive technology (ART) cycles.

DESIGN

Retrospective case control study.

SETTING

Assisted reproductive technology program at North Shore University Hospital.

PATIENTS, PARTICIPANTS

All patients undergoing an ART cycle in 1990 whose husbands did not have significant antisperm antibodies in the semen. Thirty-four female patients had significant antisperm antibodies level in the serum (antisperm antibodies-significant); 62 patients with no antibodies or nonsignificant levels constituted the control group (antisperm antibodies-negative). Incubation media were prepared with maternal serum in 37 of the antisperm antibodies-negative and in 10 of the antisperm antibodies-positive patients, whereas donor's serum (DS) was used for 25 and 24 patients, respectively.

MAIN OUTCOME MEASURES

Fertilization rate and clinical PR, defined as an intrauterine sac by transvaginal ultrasonography, were recorded for each group.

RESULTS

Analysis of variance showed a significant interaction between antisperm antibodies grouping and the type of media used, with fertilization rate in antisperm antibodies-significant patients significantly higher with maternal serum than with DS, whereas fertilization rate in antisperm antibodies-negative was quantitatively, though not statistically lower with maternal serum than with DS. When maternal serum was used, fertilization was higher in antisperm antibodies-significant than antisperm antibodies-negative. Of 29 clinical pregnancies, 11 were in antisperm antibodies-significant and 18 in antisperm antibodies-negative. In 10 of the pregnancies, maternal serum was used, whereas in 19 pregnancies DS was used. No variable was significantly predictive of pregnancy in the logistic regression analysis.

CONCLUSIONS

[1] Female patients with significant levels of antisperm antibodies in the serum had similar fertilization rates as patients with nonsignificant levels if DS was used. [2] The use of maternal serum in antisperm antibodies-significant patients did not result in inferior fertilization rates or the occurrence of pregnancy. [3] These findings suggest that a female antisperm antibodies may not hinder fertilization in vitro. [4] This study questions the value of routine screening of female serum for antisperm antibodies in ART.

SAW devices for consumer communication applications

An overview of surface acoustic wave (SAW) filter techniques available for different applications is given. Techniques for TV IF applications are outlined, and typical structures are presented. This is followed by a discussion of applications for SAW resonators. Low-loss devices for mobile communication systems and pager applications are examined. Tapped delay lines (matched filters) and convolvers for code-division multiaccess (CDMA) systems are also covered. Although simulation procedures are not considered, for many devices the theoretical frequency response is presented along with the measurement curve.

Efficient analysis tool for coupled-SAW-resonator filters

The advantages of the coupled-mode (COM) formalism and the transmission-matrix approach are combined in order to create exact and computationally efficient analysis and synthesis tools for the design of coupled surface acoustic wave resonator filters. The models for the filter components, in particular gratings, interdigital transducers (IDTs) and multistrip couplers (MSCs), are based on the COM approach that delivers closed-form expressions. To determine the pertinent COM parameters, the COM differential equations are solved and the solution is compared with analytically derived expressions from the transmission-matrix approach and the Green's function method. The most important second-order effects, such as energy storage, propagation loss, and mechanical and electrical loading, are fully taken into account. As an example, a two-pole, acoustically coupled resonator filter at 914.5 MHz on AT quartz is investigated. Excellent agreement between theory and measurement is found.

Behavioral and emotional factors and treatment responses in a study of anovulatory infertile women

In a controlled treatment study of 49 anovulatory infertile women, responses to clomiphene citrate (CC) and placebo treatments were compared and associations of behavioral and emotional factors with treatment responses were investigated. In the first treatment series, ovulation occurred in 20 of 24 women in the CC group and 8 of 22 women in the placebo group. Pregnancy was achieved by 11 women during CC treatment and 3 women during placebo treatment. Overall, 28 women completed the protocol and 21 withdrew. Those who achieved pregnancy (n = 14) did not differ significantly from the ovulation-only group (n = 22) on pretreatment measures of emotional, behavioral, and personality factors including the Hopkins Symptom Checklist (HSCL-90), Eysenck Personality Inventory, Langner Screening Scale, Mood Analog Scale, Social Adjustment Scale, Mooney Problem Checklist, and the Minnesota Multiphasic Personality Inventory (MMPI). Conclusions were that a placebo response was observed in both ovulation and pregnancy, but psychologic factors as measured in this sample were not associated with these treatment outcomes.