Mental health-related telemedicine interventions for pregnant women and new mothers: a systematic literature review.

BACKGROUND: Pregnancy and the postpartum period are times when women are at increased risk for depression and mental problems. This may also negatively affect the foetus. Thus, there is a need for interventions with low-threshold access and care. Telemedicine interventions are a promising approach to address these issues. This systematic literature review examined the efficacy of telemedicine interventions for pregnant women and/or new mothers to address mental health-related outcomes. The primary objective was to analyse whether telemedicine interventions can reduce mental health problems in pregnant women and new mothers. The secondary aim was to clarify the impact of type of interventions, their frequency and their targets. METHODS: Inclusion criteria: randomized controlled trials, with participants being pregnant women and/or new mothers (with infants up to twelve months), involving telemedicine interventions of any kind (e.g. websites, apps, chats, telephone), and addressing any mental health-related outcomes like depression, postnatal depression, anxiety, stress and others. Search terms were pregnant women, new mothers, telemedicine, RCT (randomised controlled trials), mental stress as well as numerous synonyms including medical subject headings. The literature search was conducted within the databases PubMed, Cochrane Library, Web of Science and PsycINFO. Screening, inclusion of records and data extraction were performed by two researchers according to the PRISMA guidelines, using the online tool CADIMA. RESULTS: Forty four articles were included. A majority (62%) reported significantly improved mental health-related outcomes for participants receiving telemedicine interventions compared to control. In particular (internet-delivered) Cognitive Behavioural Therapy was successful for depression and stress, and peer support improved outcomes for postnatal depression and anxiety. Interventions with preventive approaches and interventions aimed at symptom reduction were largely successful. For the most part there was no significant improvement in the symptoms of anxiety. CONCLUSION: Telemedicine interventions evaluated within RCTs were mostly successful. However, they need to be designed to specifically target a certain mental health issue because there is no one-size-fits-all approach. Further research should focus on which specific interventions are appropriate for which mental health outcomes in terms of intervention delivery modes, content, target approaches, etc. Further investigation is needed, in particular with regard to anxiety.

[Differences in Billing Patterns Between GPs and Pediatricians Using Early Diagnostics in Children and Adolescents as an Example: Analysis of Nationwide Data from Statutory Health Insurance Physicians]. / Kompensation von Leistungen zwischen Hausärzten und Kinder- und Jugendmedizinern am Beispiel der Früherkennungsuntersuchungen bei Kindern und Jugendlichen ­ Analyse von bundesweiten KBV-Daten.

BACKGROUND: Despite a 13.1% increase in the number of pediatricians between 2011 - 2020, the capacity of pediatric care has largely stagnated. This is due to increasing flexibility in working hours and a declining willingness of doctors to establish practices. In addition, there is an imbalance in the distribution of pediatric medical care capacities. While metropolitan areas are often characterized by oversupply, there is an increasing shortage of pediatricians, especially in rural areas. As a result, general practitioners in rural areas are increasingly taking over part of pediatric care. We quantify this compensation effect using the example of examinations of general health and normal child development (U1-U9). METHODS: Basis of the analysis was the Doctors' Fee Scale within the Statutory Health Insurance Scheme (Einheitlicher Bewertungsmaßstab, EBM) from 2015 (4th quarter). Nationwide data from the National Association of Statutory Health Insurance Physicians (KBV) for general practitioners and pediatricians from 2015 was evaluated. In the first step, the EBM was used to determine the potential overlap of services between the two groups of doctors. The actual compensation between the groups was quantified using general health and normal child development as an example. RESULTS: In section 1.7.1 (early detection of diseases in children) of the EBM, there is a list of 16 options for services that can be billed (fee schedule positions, GOP) by general practitioners and pediatricians. This particularly includes child examinations U1 to U9. The analysis of the national data of the KBV for the early detection of diseases in children showed significant differences between rural and urban regions in the billing procedure. Nationwide, general practitioners billed 6.6% of the services in the area of early detection of diseases in children in 2015. In rural regions this share was 23% compared to 3.6% in urban regions. The analysis of the nationwide data showed that the proportion of services billed by general practitioners was higher in rural regions than in urban regions. CONCLUSION: The EBM allows billing of services by both general practitioners and pediatricians, especially in the area of general GOP across all medical groups. The national billing data of the KBV shows that general practitioners in rural regions bill more services from the corresponding sections than in urban regions.

[Tandem Practices: Pediatric Consultation Hours in General Practitioners' Practices in Rural Areas in Germany - a Collaborative Project]. / Tandem-Praxen ­ Pädiatrische Sprechstunden in Hausarzt-Praxen in ländlichen Regionen: ein Kooperations-Experiment.

BACKGROUND: In Germany, patients under the age of 18 receive medical care from pediatricians. In sparsely populated regions, general practitioners often have to do the job of pediatricians and offer medical care to children, which in most cases is adequate. However, it does not meet the goal of demand planning namely, every patient should have equal access to care regardless of their place of residence. One option to help achieve this is the implementation of consultation hours with pediatricians in general practitioners' practices (tandem practices). The aim of this study was to investigate the feasibility and acceptance of this cooperation and whether this improved access to pediatric care. METHODS: First, general practitioners willing to participate were identified, where the nearest pediatrician's practice was more than 20 kilometers away. The second step was to find suitable pediatricians willing to offer regular weekly pediatric consultations in the practice of a general practitioner. For the evaluation, various data collection methods were used: one-off parent questionnaires at the time of study inclusion, questionnaires filled out by the pediatricians for each consultation, and data from the practice information systems in the participating practices. The distance between the patients' place of residence and the next regular outpatient pediatrician's practice were calculated and compared to the distance to a tandem practice. RESULTS: In April 2019, in two practices tandem consultation hours were implemented. During 12 months, 192 children and adolescents (50.2% female) were included. They attended the consultation hours a total of 387 times. Of 482 reasons given in the doctor's questionnaire, 36.9% were vaccinations (n=178), 14.9% were preventive examinations (n=72), the most frequently coded ICD-10 diagnostic groups were diseases of the respiratory system (J00-J99: 8.5%, n=41) and mental/behavioral disorders (F00-F99: 7.7%, n=37). Before the project, the patients had an average of 20.2 kilometers (min 0.3; max 34.8) to the next regular outpatient pediatrician's practice; within the project, the distance decreased to 5.1 kilometers (min 0.1; max 26.7). CONCLUSION: All doctors involved wanted to continue the tandem consultations after the end of the test phase. The project results showed the feasibility and a high level of acceptance of tandem practices, both for the doctors involved and for the patients and their parents.

Effects of Closure of the Paediatric Department of a District Hospital on Regional Care: Analysis of Patient Flows. / Auswirkungen der Schließung der pädiatrischen Abteilung eines Kreiskrankenhauses auf die regionale Versorgung ­ Analyse der Patientenflüsse.

BACKGROUND: The consequences of economization and staff shortage in the German health care system strongly affect paediatric care structures, especially in rural regions. It is not known how closures of paediatric departments influence patient flows of surrounding hospitals. Here, we investigate the quantitative effects of closure of the paediatric department of a district hospital and the subsequent opening of an alternative inpatient service on the utilisation of inpatient and outpatient care services of the two neighboring hospitals and the emergency services of the region. METHODOLOGY: In the observation period from 2015 to 2019, patient-related data from the three hospitals in the study region as well as data from the rescue service were evaluated. RESULTS: In the year after the paediatric department of the district hospital was closed in 2016, the total number of inpatient cases in the region decreased by 33% (2015: n=1,787; 2016: n=1,193) and then decreased by an additional 11% (2019: n=1,005). The number of outpatient cases decreased by further 8% (2015: n=6,250; 2019: n=5,770). In the last observation year, emergency services were used much more frequently than in the year before the closure (2015: n=398; 2019: n=572). This means an increase of 44%. CONCLUSION: After the closure of the paediatric department, the total number of inpatient cases in the region fell sharply. However, actual gaps in care apparently did not arise. Before closing, the consequences for the surrounding hospitals should be assessed more precisely. Real gaps in care must be counteracted, e. g. through alternative outpatient services.

[Attitude of Parents Towards Pediatric Care and Interprofessional Task-Sharing in Regions Distant Versus Close to Care Facilities: Results of a Standardized Survey]. / Einstellungen von Eltern zur pädiatrischen Versorgung und Delegation ärztlicher Aufgaben in versorgungsfernen und versorgungsnahen Regionen: Ergebnisse einer standardisierten Befragung.

AIM: The aim of the study was to determine parents' views in regions distant to medical care (dtmc) vs. close to medical care (ctmc) on (1) the assessment of situation in pediatric care and (2) on delegation of medical tasks to qualified members of non-medical health professions. METHOD: A self-developed questionnaire was sent to parents in kindergartens, who are either nearby (=close to the medical care provider, ctmc) or more than 20 km away from the nearest pediatric practice and a pediatrics department (=distant to the medical care provider, dtmc). The questions covered socio-demographic, pediatric-care-related aspects and attitudes to delegation of defined medical tasks to non-medical health professionals. RESULTS: Of the n=407 evaluable questionnaires (response rate: 18%), 49% came from parents in ctmc-kindergartens and 51% from parents in dtmc-kindergartens. Significant differences were found in the number of children living in the household (ctmc: 21% with 3 or more children vs. dtmc:13%; p-value 0,044), years of education of parents (ctmc: 50% had more than 10 years vs. dtmc: 39%; p-value 0.026), the number of visits to doctor (ctmc: 50% presented her child 4 or more times to a doctor in the last 12 months vs. dtmc: 32%; p-value <0.001) and the kind of medical doctor present (dtmc: in 51% a pediatrician vs. ctmc: 87%; p-value <0.001). The distance to the doctor was significantly different (p-value <0.001) and parents in dtmc-kindergartens perceived more often problems in pediatric health care (dtmc: 61% confirmed problems vs. ctmc: 47%; p-value 0.032). Dtmc-kindergarten-parents more often approved delegation for all of the defined and proposed medical tasks. CONCLUSIONS: The results show clear differences between the survey regions. To support pediatric care in regions distant to medical care facilities, innovative care concepts are needed. The positive attitude of the majority of parents on the subject of delegation forms a good basis for the development of concrete concepts and their practical testing in pilot projects.

[Utilization of Gynaecological Cancer Screening by Women 20 to 35 Years of Age Receiving Unemployment Benefits Under Social Security Code II]. / Die Inanspruchnahme gynäkologischer Krebsfrüherkennungsuntersuchungen bei 20- bis 35-jährigen Frauen mit Bezug sozialer Transferleistungen nach Sozialgesetzbuch II.

The aim of the study was to analyze associations between utilization of gynaecological cancer screening (GCS) and the number of months during which state unemployment benefits (Social Security Code II) were drawn by women aged 20 to 35 years. The sample included 223 women with complete interview data (participation rate: 69%). The findings show that more women drawing unemployment benefits for a short-term (<12 months) utilized GCS compared to those receiving long-term benefits (>36 months).

Association between the use of free-of-charge intrauterine devices and a history of induced abortion: a retrospective study.

BACKGROUND: To determine whether use of intrauterine device (IUD) is influenced by a history of induced abortion and the type of contraceptives used until costs are covered. METHODS: We analyzed data from 301 female residents in Mecklenburg-West Pomerania, an economically challenged community. The women, aged between 20 and 35 years, were entitled to receive unemployment benefits, and had access to free-of-charge oral contraceptives, ring or IUD. Cross-sectional data were analyzed using logistic regression. RESULTS: There were 112 (37.2%) women with a history of induced abortion, and 46 (15.3%) reported exclusively using less effective contraceptives (e.g. condoms). In a univariate logistic regression, use of an IUD was associated with a history of having had an induced abortion. Furthermore, uptake of an IUD was associated with women who had, until costs were covered, exclusively choice to use less effective contraceptives (OR = 3.281, 95% CI: 1.717; 6.273). Both associations remained significant in a multivariate model. CONCLUSIONS: Free contraceptives provided to women receiving unemployment benefits may increase the use of IUDs, especially among those with a history of an induced abortion and those using less effective contraceptives.

[The use of free-of-charge prescription contraceptives among women : Results of a pilot project in the German federal state of Mecklenburg-Western Pomerania]. / Inanspruchnahme kostenfreier verschreibungspflichtiger Verhütungsmittel durch Frauen : Ergebnisse eines Modellprojekts in Mecklenburg-Vorpommern.

BACKGROUND: There is a connection between the receipt of unemployment benefits and the failure to use contraceptives in Germany. This study aims to understand the use of contraceptives among women entitled to unemployment benefits under the Sozialgesetzbuch II or XII (SGB II or SGB XII), prior and during an offer of contraceptives free of charge (CFOC). METHODS: The criteria for the use of CFOC (pill, intrauterine device, or ring) over a 12-month period were: age between 20 and 35 years, resident in predefined urban or rural postal codes in the German federal state of Mecklenburg-Western Pomerania, and participation in a self-administered survey. Data about participants' age, education, number of children, relationship status, period of payment according to SGB II or SGB XII, the use and barriers to use of contraceptives during every occurrence of sexual intercourse, as well as the kind of contraceptives used. RESULTS: From a total of 418 women: 40.9% were single-mothers, 39.0% did not graduate school, 21.1% were childless, and 57.9% had received unemployment benefits for at least three years. Further, 21.1% rated their type of contraceptive as "less safe" or "unsafe." The most commonly cited reasons for nonregular use of contraceptives were: they are too expensive or their use is forgotten. A change in contraceptives was made by 30.9% due to the offer of CFOC. The change was associated with the number of children and the exclusive use of less safe contraceptives. DISCUSSION: CFOC seems to be attractive, especially for women with children and those who receive long-term unemployment benefits. Changing demands concerning the safety of birth control during the lives of women should be considered in the discussion about common rules for the access to CFOC.

Testing clinical competencies in undergraduate nursing education using Objective Structured Clinical Examination (OSCE) ­ a literature review of international practice / Objective Structured Clinical Examination (OSCE) als kompetenz-orientiertes Prüfungsinstrument in der pflegerischen Erstausbildung - eine Literaturanalyse zu ihrer internationalen Anwendung

Background: In response to demographic trends in Germany nursing competencies are currently reevaluated. Since these have to be taught and trained in nursing education programs, efficient verification of the success is necessary. OSCEs are internationally well-recognized as a comprehensive tool for that. Aim: In this analysis we identified competencies worldwide, which are tested by OSCEs in undergraduate nursing education programs. Method: An international literature research was conducted. The selection criterion for an article was the specification of at least one verifiable competency. Afterwards the competencies were categorized into knowledge, skills and attitudes according to the German "Fachqualifikationsrahmen Pflege für die hochschulische Bildung". Results: A total of 36 publications fulfilled all inclusion criteria. Relevant studies were predominantly initiated in the UK, Canada and Australia. Within all categories a total of n = 166 different competencies are mentioned. OSCEs are developed and performed in a broad range of methods. Most frequently skills were verified. The most common topic was sure handling of medication. Other important themes were communicative competencies in relation to patients and the ability of self-evaluation. Discussion/Conclusions: A variation in examination methods is appropriate as different competencies are acquired in preparation of the test. Evaluation took place on an individual or institutional level. Further research is needed.

Evaluation of a Health Information Exchange System for Geriatric Health Care in Rural Areas: Development and Technical Acceptance Study.

BACKGROUND: Patients of geriatrics are often treated by several health care providers at the same time. The spatial, informational, and organizational separation of these health care providers can hinder the effective treatment of these patients. OBJECTIVE: This study aimed to develop a regional health information exchange (HIE) system to improve HIE in geriatric treatment. This study also evaluated the usability of the regional HIE system and sought to identify barriers to and facilitators of its implementation. METHODS: The development of the regional HIE system followed the community-based participatory research approach. The primary outcomes were the usability of the regional HIE system, expected implementation barriers and facilitators, and the quality of the developmental process. Data were collected and analyzed using a mixed methods approach. RESULTS: A total of 3 focus regions were identified, 22 geriatric health care providers participated in the development of the regional HIE system, and 11 workshops were conducted between October 2019 and September 2020. In total, 12 participants responded to a questionnaire. The main results were that the regional HIE system should support the exchange of assessments, diagnoses, medication, assistive device supply, and social information. The regional HIE system was expected to be able to improve the quality and continuity of care. In total, 5 adoption facilitators were identified. The main points were adaptability of the regional HIE system to local needs, availability to different patient groups and treatment documents, web-based design, trust among the users, and computer literacy. A total of 13 barriers to adoption were identified. The main expected barriers to implementation were lack of resources, interoperability issues, computer illiteracy, lack of trust, privacy concerns, and ease-of-use issues. CONCLUSIONS: Participating health care professionals shared similar motivations for developing the regional HIE system, including improved quality of care, reduction of unnecessary examinations, and more effective health care provision. An overly complicated registration process for health care professionals and the patients' free choice of their health care providers hinder the effectiveness of the regional HIE system, resulting in incomplete patient health information. However, the web-based design of the system bridges interoperability problems that exist owing to the different technical and organizational structures of the health care facilities involved. The regional HIE system is better accepted by health care professionals who are already engaged in an interdisciplinary, geriatric-focused network. This might indicate that pre-existing cross-organizational structures and processes are prerequisites for using HIE systems. The participatory design supports the development of technologies that are adaptable to regional needs. Health care providers are interested in participating in the development of an HIE system, but they often lack the required time, knowledge, and resources.

Triage through telemedicine in paediatric emergency care-Results of a concordance study.

BACKGROUND: In the German health care system, parents with an acutely ill child can visit an emergency room (ER) 24 hours a day, seven days a week. At the ER, the patient receives a medical consultation. Many parents use these facilities as they do not know how urgently their child requires medical attention. In recent years, paediatric departments in smaller hospitals have been closed, particularly in rural regions. As a result of this, the distances that patients must travel to paediatric care facilities in these regions are increasing, causing more children to visit an ER for adults. However, paediatric expertise is often required in order to assess how quickly the patient requires treatment and select an adequate treatment. This decision is made by a doctor in German ERs. We have examined whether remote paediatricians can perform a standardised urgency assessment (triage) using a video conferencing system. METHODS: Only acutely ill patients who were brought to a paediatric emergency room (paedER) by their parents or carers, without prior medical consultation, have been included in this study. First, an on-site paediatrician assessed the urgency of each case using a standardised triage. In order to do this, the Paediatric Canadian Triage and Acuity Scale (PaedCTAS) was translated into German and adapted for use in a standardised IT-based data collection tool. After the initial on-site triage, a telemedicine paediatrician, based in a different hospital, repeated the triage using a video conferencing system. Both paediatricians used the same triage procedure. The primary outcome was the degree of concordance and interobserver agreement, measured using Cohen's kappa, between the two paediatricians. We have also included patient and assessor demographics. RESULTS: A total of 266 patients were included in the study. Of these, 227 cases were eligible for the concordance analysis. In n = 154 cases (68%), there was concordance between the on-site paediatrician's and telemedicine paediatrician's urgency assessments. In n = 50 cases (22%), the telemedicine paediatrician rated the urgency of the patient's condition higher (overtriage); in 23 cases (10%), the assessment indicated a lower urgency (undertriage). Nineteen medical doctors were included in the study, mostly trained paediatric specialists. Some of them acted as an on-site doctor and telemedicine doctor. Cohen's weighted kappa was 0.64 (95% CI: 0.49-0.79), indicating a substantial agreement between the specialists. CONCLUSIONS: Telemedical triage can assist in providing acute paediatric care in regions with a low density of paediatric care facilities. The next steps are further developing the triage tool and implementing telemedicine urgency assessment in a larger network of hospitals in order to improve the integration of telemedicine into hospitals' organisational processes. The processes should include intensive training for the doctors involved in telemedical triage. TRIAL REGISTRATION: DRKS00013207.

Task-Sharing Between Pediatricians and Non-Physician Healthcare Professionals in Outpatient Child Health Care in Germany: Assessment of Need and Acceptance for Concept Development.

Although pediatricians in Germany work as general practitioners for children, they are planned and trained as medical specialists. In consequence, distances between practices and residences of patients can be very large. The implementation of task-sharing models is a promising option to sustain pediatric outpatient care in rural regions. In this study we assessed the need for and acceptance of delegation of tasks in outpatient pediatric healthcare to non-physician healthcare professionals and developed a task-sharing concept. A standardized questionnaire was developed and addressed a wide range of healthcare professionals. On the basis of the results of the questionnaire and a subsequent workshop involving representatives of the various fields of pediatric care a delegation-concept was developed. A total of 206 questionnaires were answered (response rate: 17%). About 70% of the respondents (n = 145) agreed with the delegation of counseling on prevention, 66% (n = 135) with the delegation of tasks in the transition process into adult medicine. All proposed tasks were conceivable for at least a third of the respondents. Mostly, pediatricians could envision delegation more than the non-physician health care professionals. A three-dimension-delegation-concept was developed: which tasks can be delegated to whom in which setting. Basically, if nurses or medical practice assistants are adequately qualified, all tasks can be delegated to both. The delegation was approved by most of the respondents. Implementation of task-sharing provides a new option to support pediatricians and create better access to outpatient pediatric health care in rural regions. The next step should be the implementation of the delegation concept in pilot projects.

[Geriatric care in rural areas: Results from two standardized surveys of care providers]. / Geriatrische Versorgung in ländlichen Regionen: Ergebnisse aus zwei standardisierten Befragungen von Leistungserbringern und Akteuren.

BACKGROUND: Due to a growing elderly population the number of age-related diseases increases and thus the need for geriatric care. In rural areas with low population density and few healthcare providers there is a risk of inadequate care. AIM OF THE STUDY: The aim of our investigation was to identify gaps in care and preferred improvement approaches in rural areas from the perspective of local care providers. METHODS: 1,545 healthcare providers from two rural regions were surveyed on the care situation (assessment according to the German school grading system), improvement approaches and problems (simple frequencies). The participants' answers were categorized and analyzed by their work location according to the central-place concept of high-order, middle-order and lower-order (basic) centers. RESULTS: 348 healthcare providers participated (response rate: 22.5 %). The outpatient and inpatient care situation in geriatrics was rated "satisfactory" on average. Geriatric care is most often jeopardized by long waiting times for specialist treatment (71.0 %). Significant differences in the rating were found in the coverage of geriatric care by inpatient care (p=0.0018) and the accessibility of medical facilities by public transport (p=<0.001). These were better rated in the higher-order centers. The preferred approach to improve care was intersectoral networking (62.3 %) among care providers. CONCLUSIONS: In rural areas, supply problems in geriatrics exist, in particular accessibility and waiting times in middle-order and basic centers. Solutions of regional, intersectoral and interprofessional care were approved by a majority of the participants.

Environmental fate and global distribution of polychlorinated biphenyls.

In recent decades, regulators, academia, and industry have all paid increasing attention to the crucial task of determining how xenobiotic exposures affect biota populations, communities, or entire ecosystems. For decades, PCBs have been recognized as important and potentially harmful environmental contaminants. The intrinsic properties of PCBs, such as high environmental persistence, resistance to metabolism in organisms, and tendency to accumulate in lipids have contributed to their ubiquity in environmental media and have induced concern for their toxic effects after prolonged exposure. PCBs are bioaccumulated mainly by aquatic and terrestrial organisms and thus enter the food web. Humans and wildlife that consume contaminated organisms can also accumulate PCBs in their tissues. Such accumulation is of concern, because it may lead to body burdens of PCBs that could have adverse health effects in humans and wildlife. PCBs may affect not only individual organisms but ultimately whole ecosystems. Moreover, PCBs are slower to biodegrade in the environment than are many other organic chemicals. The low water solubility and the low vapor pressure of PCBs, coupled with air, water, and sediment transport processes, means that they are readily transported from local or regional sites of contamination to remote areas. PCBs are transformed mainly through microbial degradation and particularly reductive dechlorination via organisms that take them up. Metabolism by microorganisms and other animals can cause relative proportions of some congeners to increase while others decrease. Because the susceptibility of PCBs to degradation and bioaccumulation is congener-specific, the composition of PCB congener mixtures that occur in the environment differs substantially from that of the original industrial mixtures released into the environment. Generally, the less-chlorinated congeners are more water soluble, more volatile, and more likely to biodegrade. On the other hand, high-chlorinated PCBs are often more resistant to degradation and volatilization and sorb more strongly to particulate matter. Some more-chlorinated PCBs tend to bioaccumulate to greater concentrations in tissues of animals than do low-molecular-weight ones. The more-heavily chlorinated PCBs can also biomagnify in food webs. Other high-molecular-weight congeners have specific structures that render them susceptible to metabolism by such species as fish, crustacea, birds, and mammals. In recent years, there has been substantial progress made in understanding the human health and ecological effects of PCBs and their environmental dynamics. However, risk assessments based only on the original PCB mixture that entered the environment are not sufficient to determine either (1) the persistence or toxicity of the weathered PCB mixture actually present in the environment, or (2) the risks to humans and the ecosystem posed by the weathered mixture. In this paper, we have reviewed the status of current knowledge on PCBs with regard to environmental inputs, global distribution, and environmental fate. We conclude that to know and understand the critical environmental fate pathways for PCBs, both a combination of field studies in real ecosystems and more controlled laboratory investigations are needed. For the future, both revised and new models on how PCBs behave in the environment are needed. Finally, more information on ow PCBs affect relevant physiological and behavioral characteristics of organisms tha are susceptible to contamination are needed.

Methods for determining pesticides and polychlorinated biphenyls in food samples--problems and challenges.

Determination of residual amounts of pesticides and polychlorinated biphenyls (PCBs) in food samples requires the use of specific techniques regarding sample preparation as well as instrumental analysis which should be characterized by a very low detection limit. A problem associated with the use of pesticides and PCBs is the need for controlling their residues in the environment, particularly in food, as these chemicals show a propensity to accumulate. The analysis of food samples for the presence of pesticides and PCBs brings on many difficulties because of the specificity of sample preparation consisting of multistep purification procedures of samples that contain trace amounts of an analyte. Concentration determinations of pollutants that easily dissolve in complex matrices, particularly in the presence of a large apportionment of interfering substances, pose a big challenge. Therefore, the basic step in food analysis for the presence of pesticides and PCBs is sample preparation which mainly consists of analyte enrichment and the removal of interfering substances. But all steps of the analytical procedure that include sample collection and preparation, extraction of analytes from matrix, extract purification, and final determination, are very significant; their precision and correct application have a decisive effect on the final result.

Applications of sample preparation techniques in the analysis of pesticides and PCBs in food.

Pesticides and polychlorinated biphenyls (PCBs) are found in various parts of the environment in quite small concentrations, but they accumulate and thus become a threat to human health and life. A review is focused on the application of some popular techniques for sample preparation in analysis of these compounds in food. Even with the emergence of advanced techniques of final analysis, complex matrices, such as food, require extensive sample extraction and purification. Traditional sample preparation techniques are time consuming and require large amount of solvents, which are expensive, generate considerable waste, contaminate the sample and can enrich it for analytes. There have been many sample preparation techniques proposed to meet the requirements connected with the multiplicity of food. Optimal sample preparation can reduce analysis time, sources of error, enhance sensitivity and enable unequivocal identification and quantification. Sample extraction and purification techniques are discussed and their most recent applications in food analysis are provided. This review pointed out that sample preparation is the critical step.