Threshold of toxicological concern for chemical substances present in the diet: a practical tool for assessing the need for toxicity testing

Critical comparison of BMD and TD50 methods for the calculation of acceptable intakes for N-nitroso compounds

The tumorigenic dose 50 (TD50) is a widely used measure of carcinogenic potency which has historically been used to determine acceptable intake limits for carcinogenic compounds. Although broadly used, the TD50 model was not designed to account for important biological factors such as DNA repair and cell compensatory mechanisms, changes in absorption, etc., leading to the development of benchmark dose (BMD) approaches, which use more flexible dose-response models that are better able to account for these processes. Using a nitrosamine dataset as a case study, we compare the impact of moving to a BMD-based limit as opposed to a TD50-based limit. Although there are differences in individual potency estimates between the two approaches for some compounds, we show that the key metrics such as the 5th percentile of the respective potency distributions, used when calculating class-specific default acceptable intakes, are not greatly affected. Furthermore, potency estimates for nitrosamine compounds relevant to read-across do not vary by more than a factor of 3, which is little in the context of the inherent variability in a biological response, in an overall landscape wherein potencies can vary by four orders of magnitude. This suggests a move to BMD-based limits is achievable without significant disruption to existing limits while utilising a more robust methodology.

Control of N-nitrosamine impurities in drug products: Progressing the current CPCA framework and supporting the derivation of robust compound specific acceptable intakes

The carcinogenic potency categorisation approach (CPCA) has recently been introduced by health authorities. In this model, structural features from recent literature, industry proposals, and analyses performed by health authorities, provide a rapid assessment of the potential acceptable intake (AI) for a nitrosamine impurity. As with other screening regulatory values (such as the ICH M7 Threshold of Toxicological Concern), the CPCA is conservative and can be considered a de minimis risk management framework. In cases where a nitrosamine drug substance-related impurity (NDSRI) is present below the CPCA limit, the framework provides resolution from a toxicological perspective (i.e., no further toxicology studies are required). Where an NDSRI is above the CPCA limit, the framework provides for the initiation of additional activities (i.e., the CPCA is not the only possible limit). Read-across approaches are described in both the CPCA and M7 guidance and can provide a limit with more specific applicability than the general model. The use of available experimental data (in vitro or in vivo), is valuable in order to provide an even more specific limit. The CPCA provides a framework; however, data should permit changing the AI from initial structural assessment, based on increasing data, to ultimately increase precision of the AI.

Pharmaceutical and Trace Metal Interaction within the Water-Soil-Plant Continuum: Implications for Human and Soil Health

Unplanned water reuse for crop irrigation may pose a global health risk due to the entry of contaminants into the food chain, undesirable effects on crop quality, and impact on soil health. In this study, we evaluate the impact derived from the co-occurrence of pharmaceuticals (Phs), trace metals (TMs), and one metalloid within the water-soil-plant continuum through bioassay experiments with Lactuca sativa L. Results indicate that the co-occurrence of Phs and TMs has synergistic or antagonistic effects, depending on target contaminants and environmental compartments. Complex formations between drugs and TMs may be responsible for enhanced sorption onto the soil of several Phs and TMs. Concerning plant uptake, the co-occurrence of Phs and TMs exerts antagonistic and synergistic effects on carbamazepine and diazepam, respectively. With the exception of Cd, drugs exert an antagonistic effect on TMs, negatively affecting their uptake and translocation. Drug contents in lettuce edible parts do not pose any threat to human health, but Cd levels exceed the maximum limits set for leafy vegetable foodstuffs. Under Ph-TM conditions, lettuce biomass decreases, and a nutrient imbalance is observed. Soil enzyme activity is stimulated under Ph-TM conditions (β-galactosidase) and Ph and Ph-TM conditions (urease and arylsulfatase), or it is not affected (phosphatase).

The impact of surface functionalization of cellulose following simulated digestion and gastrointestinal cell-based model exposure

Surface-functionalized cellulose materials are developed for various purposes, including food additives and food contact materials. A new biologically relevant testing strategy has been developed based on guidance from the European Food Safety Authority to demonstrate the safety of several next-generation surface-functionalized cellulose materials. This strategy involves a complex three-stage simulated digestion to compare the health effects of thirteen novel different types of cellulose. The physical and chemical properties of surface-functionalized fibrillated celluloses differed depending on the type, amount, and location of functional groups such as sulfonate, TEMPO-oxidized carboxy, and periodate-chlorite oxidized dicarboxylic acid celluloses. Despite exposure to gastrointestinal fluids, the celluloses maintained their physicochemical properties, such as negative surface charges and high length-to-width/thickness aspect ratios. An established intestinal co-culture model was used to measure cytotoxicity, barrier integrity, oxidative stress, and pro-inflammatory response to create a toxicological profile for these unique materials. We conclude that the C6 carboxylated cellulose nanofibrils by TEMPO-oxidation induced the most toxicity in the biological model used in this study and that the observed effects were most prominent at the 4-hour post-exposure time point.

FEMA GRAS assessment of natural flavor complexes: Sage oil, Orris Root Extract and Tagetes Oil and related flavoring ingredients

In recent years, the Expert Panel of the Flavor and Extract Manufacturers Association (FEMA) has conducted a program to re-evaluate the safety of natural flavor complexes (NFCs) used as flavor ingredients. This publication, twelfth in the series, details the re-evaluation of NFCs whose constituent profiles are characterized by alicyclic or linear ketones. In its re-evaluation, the Expert Panel applies a scientific constituent-based procedure for the safety evaluation of NFCs in commerce using a congeneric group approach. Estimated intakes of each congeneric group of the NFC are evaluated using the well-established and conservative Threshold of Toxicological Concern (TTC) approach. In addition, studies on the toxicity and genotoxicity of members of the congeneric groups and the NFCs under evaluation are reviewed. The scope of the safety evaluation of the NFCs contained herein does not include added use in dietary supplements or any products other than food. Thirteen (13) NFCs derived from the Boronia, Cinnamomum, Thuja, Ruta, Salvia, Tagetes, Hyssopus, Iris, Perilla and Artemisia genera are affirmed as generally recognized as safe (GRAS) under conditions of their intended use as flavor ingredients based on an evaluation of each NFC and the constituents and congeneric groups therein.

The safety assessment of tampons: illustration of a comprehensive approach for four different products

Introduction

We illustrate a comprehensive tampon safety assessment approach that assures products can be used safely. Material biocompatibility, vaginal mucosa assessment, vaginal microbiome evaluation, and in vitro assessment of potential risk of staphylococcal toxic shock syndrome expressed through growth of Staphylococcus aureus (S. aureus) and production of TSST-1 are the four essential portions of the approach. Post-marketing surveillance informs of possible health effects that warrant follow up. The approach meets or exceeds US and international regulatory guidance and is described through the example of four tampon products.

Methods/Results

Each product is comprised mostly of large molecular weight components (cotton, rayon, polymers) that cannot pass the vaginal mucosa, are widely used across the industry, and replete with a vast body of safety data and a long history of safe use in the category. Quantitative risk assessment of all small molecular weight components assured a sufficient margin of safety supporting their use. Vaginal mucosa assessment confirmed that pressure points, rough edges and/or sharp contact points were absent. A randomized cross-over clinical trial (ClinicalTrials.gov Identifier: NCT03478371) revealed favorable comfort ratings, and few complaints of irritation, burning, stinging, or discomfort upon insertion, wear, and removal. Adverse events were few, mild in severity, self-limited and resolved without treatment. Vaginal microbiota assessment in vitro presented no adverse effect on microbial growth. Culture-independent microbiome analyses from vaginal swab samples obtained during the clinical trial showed no differences attributable to tampon usage, but instead due to statistically significant subject-to-subject variability. Growth of S. aureus and TSST-1 toxin production in the presence of any of the four products in vitro were statistically significantly reduced when compared to medium control alone.

Discussion

The data from the four elements of the comprehensive safety assessment approach illustrated herein confirm that tampons evaluated using this system can be used safely for menstrual protection. A post-marketing surveillance system that monitors and responds to in-market experiences indicated in-use tolerability of the product among consumers, thus confirming the conclusions of the pre-marketing safety assessment.

Risk control of antibiotics, antibiotic resistance genes (ARGs) and antibiotic resistant bacteria (ARB) during sewage sludge treatment and disposal: A review

Sewage sludge is an important reservoir of antibiotics, antibiotic resistance genes (ARGs), and antibiotic resistant bacteria (ARB) in wastewater treatment plants (WWTPs), and the reclamation of sewage sludge potentially threats human health and environmental safety. Sludge treatment and disposal are expected to control these risks, and this review summarizes the fate and controlling efficiency of antibiotics, ARGs, and ARB in sludge involved in different processes, i.e., disintegration, anaerobic digestion, aerobic composting, drying, pyrolysis, constructed wetland, and land application. Additionally, the analysis and characterization methods of antibiotics, ARGs, and ARB in complicate sludge are reviewed, and the quantitative risk assessment approaches involved in land application are comprehensively discussed. This review benefits process optimization of sludge treatment and disposal, with regard to environmental risks control of antibiotics, ARGs, and ARB in sludge. Furthermore, current research limitations and gaps, e.g., the antibiotic resistance risk assessment in sludge-amended soil, are proposed to advance the future studies.

FEMA GRAS assessment of natural flavor complexes: Allspice, anise, fennel-derived and related flavoring ingredients

The FEMA Expert Panel program to re-evaluate the safety of natural flavor complexes (NFCs) used as flavoring ingredients in food has resulted in the publication of an updated constituent-based procedure as well as publications on the safety evaluation of many botanical-derived NFCs. This publication, ninth in the series and related to the ninth publication, describes the affirmation of the generally recognized as safe (GRAS) status for NFCs with propenylhydroxybenzene and allylalkoxybenzene constituents under their conditions of intended use as flavoring ingredients added to food. The Panel's procedure applies the threshold of toxicological concern (TTC) concept and evaluates relevant data on absorption, metabolism, genotoxic potential and toxicology for the NFCs themselves and their respective constituent congeneric groups. For NFCs containing allylalkoxybenzene constituent(s) with suspected genotoxic potential, the estimated intake of the individual constituent is compared to the TTC for compounds with structural alerts for genotoxicity and if exceeded, a margin of exposure is calculated using BMDL10 values derived from benchmark dose analyses using Bayesian model averaging, as presented in the tenth article of the series. Safety evaluations for NFCs derived from allspice, anise seed, star anise, sweet fennel seed and pimento leaves were conducted and their GRAS status was affirmed for use as flavoring ingredients. The scope of the safety evaluation contained herein does not include added use in dietary supplements or any products other than food.

FEMA GRAS assessment of natural flavor complexes: Lemongrass oil, chamomile oils, citronella oil and related flavoring ingredients

In 2015, the Expert Panel of the Flavor and Extract Manufacturers Association (FEMA) initiated a program for the re-evaluation of the safety of over 250 natural flavor complexes (NFCs) used as flavor ingredients. This publication, eleventh in the series, evaluates the safety of NFCs characterized by primary alcohol, aldehyde, carboxylic acid, ester and lactone constituents derived from terpenoid biosynthetic pathways and/or lipid metabolism. The Expert Panel uses the scientific-based evaluation procedure published in 2005 and updated in 2018 that relies on a complete constituent characterization of the NFC intended for commerce and organization of the constituents of each NFC into well-defined congeneric groups. The safety of the NFCs is evaluated using the well-established and conservative threshold of toxicological concern (TTC) concept in addition to data on estimated intake, metabolism and toxicology of members of the congeneric groups and for the NFC under evaluation. The scope of the safety evaluation contained herein does not include added use in dietary supplements or any products other than food. Twenty-three NFCs, derived from the Hibiscus, Melissa, Ricinus, Anthemis, Matricaria, Cymbopogon, Saussurea, Spartium, Pelargonium, Levisticum, Rosa, Santalum, Viola, Cryptocarya and Litsea genera were affirmed as generally recognized as safe (GRAS) under their conditions of intended use as flavor ingredients based on an evaluation of each NFC and the constituents and congeneric groups therein.

FEMA GRAS assessment of natural flavor complexes: Asafetida oil, garlic oil and onion oil

The Expert Panel of the Flavor and Extract Manufacturers Association (FEMA) applies its procedure for the safety evaluation of natural flavor complexes (NFCs) to re-evaluate the safety of Asafetida Oil (Ferula assa-foetida L.) FEMA 2108, Garlic Oil (Allium sativum L.) FEMA 2503 and Onion Oil (Allium cepa L.) FEMA 2817 for use as flavoring in food. This safety evaluation is part of a series of evaluations of NFCs for use as flavoring ingredients conducted by the Expert Panel that applies a scientific procedure published in 2005 and updated in 2018. Using a group approach that relies on a complete chemical characterization of the NFC intended for commerce, the constituents of each NFC are organized into well-defined congeneric groups and the estimated intake of each constituent congeneric group is evaluated using the conservative threshold of toxicological concern (TTC) concept. Data on the metabolism, genotoxic potential and toxicology for each constituent congeneric group are reviewed as well as studies on each NFC. Based on the safety evaluation, Asafetida Oil (Ferula assa-foetida L.), Garlic Oil (Allium sativum L.) and Onion Oil (Allium cepa L.) were affirmed as generally recognized as safe (GRASa) under their conditions of intended use as flavor ingredients.

FEMA GRAS assessment of derivatives of basil, nutmeg, parsley, tarragon and related allylalkoxybenzene-containing natural flavor complexes

In 2015, the Expert Panel of the Flavor and Extract Manufacturers Association (FEMA) initiated a program for the re-evaluation of the safety of over 250 natural flavor complexes (NFCs) used as flavoring ingredients in food. In this publication, tenth in the series, NFCs containing a high percentage of at least one naturally occurring allylalkoxybenzene constituent with a suspected concern for genotoxicity and/or carcinogenicity are evaluated. In a related paper, ninth in the series, NFCs containing anethole and/or eugenol and relatively low percentages of these allylalkoxybenzenes are evaluated. The Panel applies the threshold of toxicological concern (TTC) concept and evaluates relevant toxicology data on the NFCs and their respective constituent congeneric groups. For NFCs containing allylalkoxybenzene constituent(s), the estimated intake of the constituent is compared to the TTC for compounds with structural alerts for genotoxicity and when exceeded, a margin of exposure (MOE) is calculated. BMDL₁₀ values are derived from benchmark dose analyses using Bayesian model averaging for safrole, estragole and methyl eugenol using EPA's BMDS software version 3.2. BMDL₁₀ values for myristicin, elemicin and parsley apiole were estimated by read-across using relative potency factors. Margins of safety for each constituent congeneric group and MOEs for each allylalkoxybenzene constituent for each NFC were determined that indicate no safety concern. The scope of the safety evaluation contained herein does not include added use in dietary supplements or any products other than food. Ten NFCs, derived from basil, estragon (tarragon), mace, nutmeg, parsley and Canadian snakeroot were determined or affirmed as generally recognized as safe (GRAS) under their conditions of intended use as flavor ingredients based on an evaluation of each NFC and the constituents and congeneric groups therein.

Semiquantitative sensitization safety assessment of extractable and leachables associated with parenteral pharmaceutical products

Extractable and leachables (E&Ls) associated with parenteral pharmaceutical products should be assessed for patient safety. One essential safety endpoint is local or systemic sensitization. However, there are no regulatory guidelines for quantitative sensitization safety assessment of E&Ls. A semiquantitative sensitization safety assessment workflow is developed to refine the sensitization safety assessment of E&Ls associated with parenteral pharmaceutical products. The workflow is composed of two sequential steps: local skin sensitization and systemic sensitization safety assessment. The local skin sensitization step has four tiers. The output from this step is the acceptable exposure level for local sensitization (AEL_ls) and this safety threshold can be used for local sensitization safety assessment. From the derived AEL_ls, the systemic sensitization safety assessment at step 2 proceeds in 2 tiers. The output from this workflow is the derivation of acceptable exposure level for systemic sensitization (AEL_ss). When the estimated human daily exposure (HDE) is compared with the AEL_ss, the margin of exposure is calculated to determine the sensitization safety of E&Ls following parenteral administration. The current work represents an initial effort to develop a scientifically robust process for sensitization safety assessment of E&Ls associated with parenteral pharmaceutical products.

Developing an internal threshold of toxicological concern (iTTC)

BACKGROUND

Threshold of Toxicological Concern (TTC) approaches are used for chemical safety assessment and risk-based priority setting for data poor chemicals. TTCs are derived from in vivo No Observed Effect Level (NOEL) datasets involving an external administered dose from a single exposure route, e.g., oral intake rate. Thus, a route-specific TTC can only be compared to a route-specific exposure estimate and such TTCs cannot be used for other exposure scenarios such as aggregate exposures.

OBJECTIVE

Develop and apply a method for deriving internal TTCs (iTTCs) that can be used in chemical assessments for multiple route-specific exposures (e.g., oral, inhalation or dermal) or aggregate exposures.

METHODS

Chemical-specific toxicokinetics (TK) data and models are applied to calculate internal concentrations (whole-body and blood) from the reported administered oral dose NOELs used to derive the Munro TTCs. The new iTTCs are calculated from the 5th percentile of cumulative distributions of internal NOELs and the commonly applied uncertainty factor of 100 to extrapolate animal testing data for applications in human health assessment.

RESULTS

The new iTTCs for whole-body and blood are 0.5 nmol/kg and 0.1 nmol/L, respectively. Because the iTTCs are expressed on a molar basis they are readily converted to chemical mass iTTCs using the molar mass of the chemical of interest. For example, the median molar mass in the dataset is 220 g/mol corresponding to an iTTC of 22 ng/L-blood (22 pg/mL-blood). The iTTCs are considered broadly applicable for many organic chemicals except those that are genotoxic or acetylcholinesterase inhibitors. The new iTTCs can be compared with measured or estimated whole-body or blood exposure concentrations for chemical safety screening and priority-setting.

SIGNIFICANCE

Existing Threshold of Toxicological Concern (TTC) approaches are limited in their applications for route-specific exposure scenarios only and are not suitable for chemical risk and safety assessments under conditions of aggregate exposure. New internal Threshold of Toxicological Concern (iTTC) values are developed to address data gaps in chemical safety estimation for multi-route and aggregate exposures.

Essential Oils and Melatonin as Functional Ingredients in Dogs

Simple Summary

Phytogenics are plant-based compounds with beneficial actions in feed technology and/or animal health. These so-called plant secondary metabolites are very diverse and with wide possible applications in humans and animals. Among them, essential oils (EOs) are the most used in feed for livestock and pets. Lately, melatonin has acquired new and interesting applications in dogs. Recent studies using EOs and/or melatonin in dog feeding and their involvement in health aspects are presented.

Abstract

The use of nutraceuticals or functional ingredients is increasingly widespread in human food; their use is also widespread in animal feed. These natural compounds generally come from plant materials and comprise a wide range of substances of a very diverse chemical nature. In animals, these compounds, so-called phytogenics, are used to obtain improvements in feed production/stability and also as functional components with repercussions on animal health. Along with polyphenols, isoprenoid compounds represent a family of substances with wide applications in therapy and pet nutrition. Essential oils (EOs) are a group of complex substances with fat-soluble nature that are widely used. Melatonin is an indolic amine present in all living with amphiphilic nature. In this work, we present a review of the most relevant phytogenics (polyphenol, isoprenoid, and alkaloid compounds), their characteristics, and possible uses as nutraceuticals in dogs, with special emphasis on EOs and their regulatory aspects, applied in foods and topically. Additionally, a presentation of the importance of the use of melatonin in dogs is developed, giving physiological and practical aspects about its use in dog feeding and also in topical application, with examples and future projections. This review points to the combination of EOs and melatonin in food supplements and in the topical application as an innovative product and shows excellent perspectives aimed at addressing dysfunctions in pets, such as the treatment of stress and anxiety, sleep disorders, alopecia, and hair growth problems, among others.

Toxicological assessment compilation of selected examples of raw materials for homeopathic and anthroposophic medicinal products - Part 2

The present successor article comprises more than 180 substances representing a continuative compilation of toxicologically evaluated starting materials prompted by the wide use and high number of homeopathic and anthroposophic medicinal products (HMP) on the market together with the broad spectrum of active substances of botanical, mineral, chemical or animal origin contained therein, and by the equally important requirement of applying adequate safety principles as with conventional human medicinal products in line with the European regulatory framework. The February 2019 issue of the Regulatory Toxicology and Pharmacology journal includes the antecedent article bearing the same title and entailing safety evaluations of more than 170 raw materials processed in HMP. This part 2 article highlights scientific evaluation following recognized methods used in toxicology with a view to drug-regulatory authority's assessment principles and practice in the context of HMP, and offers useful systematic, scientifically substantiated and simultaneously pragmatic approaches in differentiated HMP risk assessment. As a unique feature, both articles provide the most extensive publicly available systematic compilation of a considerable number of substances processed in HMP as a transparent resource for applicants, pharmaceutical manufacturers, the scientific community and healthcare authorities to actively support regulatory decision making in practice.

Pharmaceutical and transformation products during unplanned water reuse: Insights into natural attenuation, plant uptake and human health impact under field conditions

In urban and periurban areas, agricultural soils are often irrigated with surface water containing a complex mixture of contaminants due to wastewater treatment plant (WWTP) effluent discharges. The unplanned water reuse of these resources for crop irrigation can represent a pathway for contaminant propagation and a potential health risk due to their introduction in the food chain. The aim of this study is to provide data about the magnitude of attenuation processes and plant uptake, allowing for a reliable assessment of contaminant transfer among compartments and of the human health risk derived from unplanned water reuse activities. Target compounds are 25 pharmaceuticals, including transformation products (TPs). The field site is an agricultural parcel where maize is irrigated by a gravity-fed surface system supplied by the Jarama river, a water course strongly impacted by WWTP effluents. Throughout the 3-month irrigation period, irrigation water and water infiltrating through the vadose zone were sampled. The agricultural soil was collected before and after the irrigation campaign, and maize was sampled before harvesting. All selected compounds are detected in irrigation water (up to 12,867 ng L^-1). Metformin, two metamizole TPs and valsartan occur with the highest concentrations. For most pharmaceuticals, results demonstrate a high natural attenuation during soil infiltration (>60%). However, leached concentrations of some compounds can be still at concern level (>400 ng L^-1). A persistent behavior is observed for carbamazepine, carbamazepine epoxide and sulfamethoxazole. Pharmaceutical soil contents are in the order of ng g^-1 and positively ionized compounds accumulate more effectively. Results also indicate the presence of a constant pool of drugs in soils. Only neutral and cationic pharmaceuticals are taken up in maize tissues, mainly in the roots. There is an insignificant threat to human health derived from maize consumption however, additional toxicity tests are recommended for 4AAA and acetaminophen.

Use of the Species Sensitivity Distribution Approach to Derive Ecological Threshold of Toxicological Concern (eco-TTC) for Pesticides

The species sensitivity distribution (SSD) calculates the hazardous concentration at which 5% of species (HC5) will be potentially affected. For many compounds, HC5 values are unavailable impeding the derivation of SSD curves. Through a detailed bibliographic survey, we selected HC5 values (from acute toxicity tests) for freshwater aquatic species and 129 pesticides. The statistical distribution and variability of the HC5 values within the chemical classes were evaluated. Insecticides are the most toxic compounds in the aquatic communities (HC5 = 1.4 × 10-3 µmol L-1), followed by herbicides (HC5 = 3.3 × 10-2 µmol L-1) and fungicides (HC5 = 7.8 µmol L-1). Subsequently, the specificity of the mode of action (MoA) of pesticides on freshwater aquatic communities was investigated by calculating the ratio between the estimated baseline toxicity for aquatic communities and the HC5 experimental values gathered from the literature. Moreover, we proposed and validated a scheme to derive the ecological thresholds of toxicological concern (eco-TTC) of pesticides for which data on their effects on aquatic communities are not available. We proposed eco-TTCs for different classes of insecticides, herbicides, and fungicides with a specific MoA, and three eco-TTCs for those chemicals with unavailable MoA. We consider the proposed approach and eco-TTC values useful for risk management purposes.

FEMA GRAS assessment of natural flavor complexes: Eucalyptus oil and other cyclic ether-containing flavoring ingredients

In 2015, the Expert Panel of the Flavor and Extract Manufacturers Association (FEMA) initiated a program for the re-evaluation of the safety of over 250 natural flavor complexes (NFCs) used as flavor ingredients. This publication, the sixth in the series, will summarize the re-evaluation of eight NFCs whose constituent profiles are characterized by significant amounts of eucalyptol and/or other cyclic ethers. This re-evaluation was based on a procedure first published in 2005 and subsequently updated in 2018 that evaluates the safety of naturally occurring mixtures for their intended use as flavoring ingredients. The procedure relies on a complete chemical characterization of the NFC intended for commerce and the organization of its chemical constituents into well-defined congeneric groups. The safety of the NFC is evaluated using the well-established and conservative threshold of toxicological concern (TTC) concept in addition to data on absorption, metabolism and toxicology of the constituents of the congeneric groups and the NFC under evaluation. Eight NFCs derived from the Eucalyptus, Melaleuca, Origanum, Laurus, Rosmarinus and Salvia genera were affirmed as generally recognized as safe (GRAS) under their conditions of intended use as flavor ingredients based on an evaluation of each NFC and the constituents and congeneric groups therein.

FEMA GRAS assessment of natural flavor complexes: Origanum oil, thyme oil and related phenol derivative-containing flavoring ingredients

In 2015, the Expert Panel of the Flavor and Extract Manufacturers Association (FEMA) initiated a re-evaluation of the safety of over 250 natural flavor complexes (NFCs) used as flavor ingredients, mostly consisting of a variety of essential oils and botanical extracts. This publication, seventh in the series, re-evaluates NFCs with constituent profiles dominated by phenolic derivatives including carvacrol, thymol and related compounds using a constituent-based procedure first published in 2005 and updated in 2018. The procedure is based on the chemical characterization of each NFC as intended for commerce and the estimated intake of the constituent congeneric groups. The procedure applies the threshold of toxicological concern (TTC) concept and evaluates relevant data on absorption, metabolism, genotoxic potential and toxicology of the constituent congeneric groups and the NFC under evaluation. Herein, the FEMA Expert Panel affirmed the generally recognized as safe (GRAS) status of seven phenolic derivative-based NFCs, Origanum Oil (Extractive) (FEMA 2828), Savory Summer Oil (FEMA 3013), Savory Summer Oleoresin (FEMA 3014), Savory Winter Oil (FEMA 3016), Savory Winter Oleoresin (FEMA 3017), Thyme Oil (FEMA 3064) and Thyme White Oil (FEMA 3065) under their conditions of intended use as flavor ingredients.

Defining the Human-Biota Thresholds of Toxicological Concern for Organic Chemicals in Freshwater: The Proposed Strategy of the LIFE VERMEER Project Using VEGA Tools

Several tons of chemicals are released every year into the environment and it is essential to assess the risk of adverse effects on human health and ecosystems. Risk assessment is expensive and time-consuming and only partial information is available for many compounds. A consolidated approach to overcome this limitation is the Threshold of Toxicological Concern (TTC) for assessment of the potential health impact and, more recently, eco-TTCs for the ecological aspect. The aim is to allow a safe assessment of substances with poor toxicological characterization. Only limited attempts have been made to integrate the human and ecological risk assessment procedures in a "One Health" perspective. We are proposing a strategy to define the Human-Biota TTCs (HB-TTCs) as concentrations of organic chemicals in freshwater preserving both humans and ecological receptors at the same time. Two sets of thresholds were derived: general HB-TTCs as preliminary screening levels for compounds with no eco- and toxicological information, and compound-specific HB-TTCs for chemicals with known hazard assessment, in terms of Predicted No effect Concentration (PNEC) values for freshwater ecosystems and acceptable doses for human health. The proposed strategy is based on freely available public data and tools to characterize and group chemicals according to their toxicological profiles. Five generic HB-TTCs were defined, based on the ecotoxicological profiles reflected by the Verhaar classes, and compound-specific thresholds for more than 400 organic chemicals with complete eco- and toxicological profiles. To complete the strategy, the use of in silico models is proposed to predict the required toxicological properties and suitable models already available on the VEGAHUB platform are listed.

Screening for Ames mutagenicity of food flavor chemicals by (quantitative) structure-activity relationship

Background

(Quantitative) Structure-Activity Relationship ((Q)SAR) is a promising approach to predict the potential adverse effects of chemicals based on their structure without performing toxicological studies. We evaluate the mutagenicity of food flavor chemicals by (Q) SAR tools, identify potentially mutagenic chemicals, and verify their mutagenicity by actual Ames test.

Results

The Ames mutagenicity of 3942 food flavor chemicals was predicted using two (Q)SAR) tools, DEREK Nexus and CASE Ultra. Three thousand five hundred seventy-five chemicals (91%) were judged to be negative in both (Q) SAR tools, and 75 chemicals (2%) were predicted to be positive in both (Q) SAR tools. When the Ames test was conducted on ten of these positive chemicals, nine showed positive results.

Conclusion

The (Q) SAR method can be used for screening the mutagenicity of food flavors.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41021-020-00171-1.

FEMA GRAS assessment of natural flavor complexes: Clove, cinnamon leaf and West Indian bay leaf-derived flavoring ingredients

In 2015, the Expert Panel of the Flavor and Extract Manufacturers Association initiated the safety re-evaluation of over 250 natural flavor complexes (NFCs) used as flavor ingredients. This publication, 4th in a series focusing on the safety evaluation of NFCs, presents an evaluation of NFCs rich in hydroxyallylbenzene and hydroxypropenylbenzene constituents using a procedure initially published in 2005 and updated in 2018 that evaluates the safety of naturally occurring mixtures for their intended use as flavoring ingredients. The procedure requires the characterization of the chemical composition for each NFC and subsequent organization of the constituents into defined congeneric groups. The safety of each NFC is evaluated using the conservative threshold of toxicological concern (TTC) approach together with studies on absorption, metabolism and toxicology of the NFC and its constituent congeneric groups. By the application of this procedure, seven NFCs, derived from clove, cinnamon leaf and West Indian bay leaf were affirmed as "generally recognized as safe (GRAS)" under their conditions of intended use as flavor ingredients. An eighth NFC, an oleoresin of West Indian bay leaf, was affirmed based on its estimated intake, which is below the TTC of 0.15 μg/person per day for compounds with structural alerts for genotoxicity.

FEMA GRAS assessment of natural flavor complexes: Lavender, Guaiac Coriander-derived and related flavoring ingredients

In 2015, the Expert Panel of the Flavor and Extract Manufacturers Association (FEMA) initiated a program for the re-evaluation of the safety of over 250 natural flavor complexes (NFCs) used as flavor ingredients. This publication, fifth in the series, evaluates the safety of NFCs containing linalool and/or other characteristic mono- and sesquiterpenoid tertiary alcohols and esters using the safety evaluation procedure published by the FEMA Expert Panel in 2005 and updated in 2018. The procedure relies on a complete chemical characterization of the NFC intended for commerce and organization of the chemical constituents of each NFC into well-defined congeneric groups. The safety of each NFC is evaluated using the well-established and conservative threshold of toxicological concern (TTC) concept in addition to data on absorption, metabolism and toxicology of both the constituent congeneric groups and the NFCs. Sixteen NFCs, derived from the Lavandula, Aniba, Elettaria, Daucus, Salvia, Coriandrum, Ribes, Guaiacum/Bulnesia, Citrus, Pogostemon, Melaleuca and Michelia genera, were affirmed as generally recognized as safe (GRAS) under their conditions of intended use as flavor ingredients based on an evaluation of each NFC and the constituents and congeneric groups therein.

Cytological and Gene Profile Expression Analysis Reveals Modification in Metabolic Pathways and Catalytic Activities Induce Resistance in Botrytis cinerea Against Iprodione Isolated From Tomato

Grey mold is one of the most serious and catastrophic diseases, causing significant yield losses in fruits and vegetables worldwide. Iprodione is a broad spectrum agrochemical used as a foliar application as well as a seed protectant against many fungal and nematode diseases of fruits and vegetables from the last thirty years. The extensive use of agrochemicals produces resistance in plant pathogens and is the most devastating issue in food and agriculture. However, the molecular mechanism (whole transcriptomic analysis) of a resistant mutant of B. cinerea against iprodione is still unknown. In the present study, mycelial growth, sporulation, virulence, osmotic potential, cell membrane permeability, enzymatic activity, and whole transcriptomic analysis of UV (ultraviolet) mutagenic mutant and its wild type were performed to compare the fitness. The EC₅₀ (half maximal effective concentration that inhibits the growth of mycelium) value of iprodione for 112 isolates of B. cinerea ranged from 0.07 to 0.87 µg/mL with an average (0.47 µg/mL) collected from tomato field of Guangxi Province China. Results also revealed that, among iprodione sensitive strains, only B67 strain induced two mutants, M0 and M1 after UV application. The EC₅₀ of these induced mutants were 1025.74 μg/mL and 674.48 μg/mL, respectively, as compared to its wild type 1.12 μg/mL. Furthermore, mutant M0 showed higher mycelial growth sclerotia formation, virulence, and enzymatic activity than wild type W0 and M1 on potato dextrose agar (PDA) medium. The bctubA gene in the mutant M0 replaced TTC and GAT codon at position 593 and 599 by TTA and GAA, resulting in replacement of phenyl alanine into leucine (transversion C/A) and aspartic acid into glutamic acid (transversion T/C) respectively. In contrast, in bctubB gene, GAT codon at position 646 is replaced by AAT and aspartic acid converted into asparagine (transition G/A). RNA sequencing of the mutant and its wild type was performed without (M0, W0) and with iprodione treatment (M-ipro, W-ipro). The differential gene expression (DEG) identified 720 unigenes in mutant M-ipro than W-ipro after iprodione treatment (FDR ≤ 0.05 and log2FC ≥ 1). Seven DEGs were randomly selected for quantitative real time polymerase chain reaction to validate the RNA sequencing genes expression (log fold 2 value). The gene ontology (GO) enrichment and Kyoto encyclopedia genes and genomes (KEGG) pathway functional analyses indicated that DEG’s mainly associated with lysophopholipase, carbohydrate metabolism, amino acid metabolism, catalytic activity, multifunctional genes (MFO), glutathione-S transferase (GST), drug sensitivity, and cytochrome P450 related genes are upregulated in mutant type (M0, M-ipro) as compared to its wild type (W0, W-ipro), may be related to induce resistant in mutants of B. cinerea against iprodione.

Does the application of human waste as a fertilization material in agricultural production pose adverse effects on human health attributable to contaminants of emerging concern?

The QuEChERS (quick, easy, cheap, effective, rugged, and safe) ultrasound-assisted method was successfully used to determine the presence of contaminants of emerging concern (CECs) in both the growing medium (i.e. soil) and vegetable samples (i.e. potato, onion, celery, parsnip and carrot) cultivated in household gardens under field conditions impacted by the application of livestock manure mixed with human waste. CECs with a broad range of physico-chemical properties including pharmaceuticals, plasticizers, herbicides, personal care products, and biocides were investigated. Among all studied CECs, diclofenac (DCL), carbamazepine, bisphenol A (BPA) and estrogenic hormones (estrone (E1), 17α-ethinyl estradiol (EE2)) were detected and quantified in vegetable samples with a concentration range from 0.114 to 13.3 ng/g fresh weight (f.w.), while BPA, E1, and EE2 were detected in soil samples with concentration ranges from 0.526 to 0.830 ng/g f.w., 0.121-0.199 ng/g f.w. and 0.118-0.333 ng/g f.w., respectively. DCL was only quantified above the limit of quantification in one soil sample (0.151 ng/g f.w.). The human health risk was estimated using the threshold of toxicological concern approach and a standard diet for two segments of the population (i.e. adult and child). The consumption of investigated vegetables contaminated with CECs poses no risk for the Serbian population.

Evaluating potential refinements to existing Threshold of Toxicological Concern (TTC) values for environmentally-relevant compounds

The Toxic Substances Control Act (TSCA) mandates the US EPA perform risk-based prioritisation of chemicals in commerce and then, for high-priority substances, develop risk evaluations that integrate toxicity data with exposure information. One approach being considered for data poor chemicals is the Threshold of Toxicological Concern (TTC). Here, TTC values derived using oral (sub)chronic No Observable (Adverse) Effect Level (NO(A)EL) data from the EPA's Toxicity Values database (ToxValDB) were compared with published TTC values from Munro et al. (1996). A total of 4554 chemicals with structures present in ToxValDB were assigned into their respective TTC categories using the Toxtree software tool, of which toxicity data was available for 1304 substances. The TTC values derived from ToxValDB were similar, but not identical to the Munro TTC values: Cramer I ((ToxValDB) 37.3 c. f. (Munro) 30 μg/kg-day), Cramer II (34.6 c. f. 9.1 μg/kg-day) and Cramer III (3.9 c. f. 1.5 μg/kg-day). Cramer III 5th percentile values were found to be statistically different. Chemical features of the two Cramer III datasets were evaluated to account for the differences. TTC values derived from this expanded dataset substantiated the original TTC values, reaffirming the utility of TTC as a promising tool in a risk-based prioritisation approach.

FEMA GRAS assessment of natural flavor complexes: Mint, buchu, dill and caraway derived flavoring ingredients

In 2015, the Expert Panel of the Flavor and Extract Manufacturers Association (FEMA) initiated a re-evaluation of the safety of over 250 natural flavor complexes (NFCs) used as flavor ingredients. NFC flavor materials include a variety of essential oils and botanical extracts. The re-evaluation of NFCs is conducted based on a constituent-based procedure outlined in 2005 and updated in 2018 that evaluates the safety of NFCs for their intended use as flavor ingredients. This procedure is applied in the re-evaluation of the generally recognized as safe (GRAS) status of NFCs with constituent profiles that are dominated by alicyclic ketones such as menthone and carvone, secondary alcohols such as menthol and carveol, and related compounds. The FEMA Expert Panel affirmed the GRAS status of Peppermint Oil (FEMA 2848), Spearmint Oil (FEMA 3032), Spearmint Extract (FEMA 3031), Cornmint Oil (FEMA 4219), Erospicata Oil (FEMA 4777), Curly Mint Oil (FEMA 4778), Pennyroyal Oil (FEMA 2839), Buchu Leaves Oil (FEMA 2169), Caraway Oil (FEMA 2238) and Dill Oil (FEMA 2383) and determined FEMA GRAS status for Buchu Leaves Extract (FEMA 4923), Peppermint Oil, Terpeneless (FEMA 4924) and Spearmint Oil, Terpeneless (FEMA 4925).

Quantitative Characteristics of Toxic Compounds According to the Solvent Type

The quantitative analysis of target substances is an important part of assessing the toxicity of diverse materials. Usually, the quantitation of target compounds is conducted by instrumental analysis such as chromatography and capillary electrophoresis. If solvents are used in the pretreatment step of the target analyte quantification, it would be crucial to examine the solvent effect on the quantitative analysis. Therefore, in this study, we assessed the solvent effects using four different solvents (methanol, hexane, phosphate buffered saline (PBS), and dimethyl sulfoxide (DMSO)) and three toxic compounds (benzene, toluene, and methylisothiazolinone (MIT)). Liquid working standards containing the toxic compounds were prepared by dilution with each solvent and analyzed by gas chromatography-mass spectrometry (GC-MS). As a result, we found that the response factor (RF) values of the target analytes were different, depending on the solvent types. In particular, benzene and toluene exhibited their highest RF values (33,674 ng^-1 and 78,604 ng^-1, respectively) in hexane, while the RF value of MIT was the highest (9,067 ng^-1) in PBS. Considering the correlation (R ²) and relative standard deviation (RSD) values, all target analytes showed fairly good values (R ² > 0.99 and RSD < 10%) in methanol and DMSO. In contrast, low R ² (0.0562) and high RSD (10.6%) values of MIT were detected in hexane, while benzene and toluene exhibited relatively low R ² and high RSD values in PBS (mean R ² = 0.9892 ± 0.0146 and mean RSD = 13.3 ± 4.1%). Based on these findings, we concluded that the results and reliability of the quantitative analysis change depending on the analyte and solvent types. Therefore, in order to accurately assess the toxicity of target compounds, reliable analytical data should be obtained, preferentially by considering the solvent types.

Occurrence and human health implications of chemical contaminants in vegetables grown in peri-urban agriculture

Recent studies have proven that vegetables cultivated in peri-urban areas are exposed to a greater concentration of organic microcontaminants (OMCs) and trace elements (TEs) than those grown in rural areas. In this study, the occurrence and human health risk of chemical contaminants (16 TEs and 33 OMCs) in edible parts of lettuce, tomato, cauliflower, and broad beans from two farm fields in the peri-urban area of the city of Barcelona and one rural site outside the peri-urban area were assessed. The concentration of TEs and OMCs (on fresh weight basis) ranged from non-detectable to 17.4 mg/kg and from non-detectable to 256 μg/kg, respectively. Tomato fruits showed the highest concentration of TEs and OMCs. Principal component analysis indicated that the occurrence of chemical contaminants in vegetables depended on the commodity rather than the location (peri-urban vs rural). Risk assessment using hazardous quotient (HQ) and threshold of toxicological concern (TTC) approaches showed that the risk for the consumption of target vegetables in the peri-urban area was low and similar to that observed for the rural site. Total HQ values for TEs were always below 1, and a minimum consumption of 150 g/day for children and 380 g/day for adults is required to reach the TTC due to the presence of pesticides. Further studies are needed to estimate the combined effect of TEs and OMCs on human health.

Comprehensive toxicological study over 160 processing factors of pesticides in selected fruit and vegetables after water, mechanical and thermal processing treatments and their application to human health risk assessment

The challenge of the present comprehensive toxicological study was to evaluate water, mechanical and thermal processing factors (PFs) of twenty four pesticides (acetamiprid, alpha‑cypermethrin, azoxystrobin, boscalid, bupyrimate, chlorpyrifos, chlorothalonil, cyprodinil, deltamethrin, difenoconazole, fenazaquin, fenhexamid, fludioxonil, folpet, iprodione, lambda‑cyhlothrin, metalaxyl, pirymicarb, propargite, pyraclostrobin, tetraconazole, tiophanate methyl, thiram, trifloxystrobin) in different fruit and vegetables and estimate health risk for adults and children. The water (PF = 0,09-0,94), mechanical (PF = 0,13-0,32) and thermal (PF = 0,02-0,57) technology significantly or completely reduced concentrations of twenty one active substances in broccoli, tomatoes, strawberries and black currants. Pyrethroid insecticides (alpha‑cypermethrin, deltamethrin and lambda‑cyhalothrin) exhibited PF above one in berries influenced by high temperatures. Comprehensive processing factor database technology/pesticide/matrix (over 160 PFs) for 24 pesticides in selected fruit and vegetable species after different processing treatments was created. This paper for the first time compares health risk assessments of acute and chronic of two subpopulations of adults and the most critical group of small children using two mathematical models, without (I) and with including (II) calculated PF values. More realistic estimation of the dietary intakes of the pesticides was achieved using PFs. The hazard quotients (HQs) estimated from chronic and acute dietary exposure (Model l) were above 20% and after intake correction (Model II) were reduced to HQs = 11.5% after water, 3% mechanical and 9.5% thermal treatment.

FEMA GRAS assessment of natural flavor complexes: Citrus-derived flavoring ingredients

In 2015, the Expert Panel of the Flavor and Extract Manufacturers Association (FEMA) initiated a re-evaluation of the safety of over 250 natural flavor complexes (NFCs) used as flavoring ingredients. This publication is the first in a series and summarizes the evaluation of 54 Citrus-derived NFCs using the procedure outlined in Smith et al. (2005) and updated in Cohen et al. (2018) to evaluate the safety of naturally-occurring mixtures for their intended use as flavoring ingredients. The procedure relies on a complete chemical characterization of each NFC intended for commerce and organization of each NFC's chemical constituents into well-defined congeneric groups. The safety of the NFC is evaluated using the well-established and conservative threshold of toxicological concern (TTC) concept in addition to data on absorption, metabolism and toxicology of members of the congeneric groups and the NFC under evaluation. As a result of the application of the procedure, 54 natural flavor complexes derived from botanicals of the Citrus genus were affirmed as generally recognized as safe (GRAS) under their conditions of intended use as flavoring ingredients based on an evaluation of each NFC and the constituents and congeneric groups therein.

How does dose impact on the severity of food-induced allergic reactions, and can this improve risk assessment for allergenic foods?: Report from an ILSI Europe Food Allergy Task Force Expert Group and Workshop

Quantitative risk assessment (QRA) for food allergens has made considerable progress in recent years, yet acceptability of its outcomes remains stymied because of the limited extent to which it has been possible to incorporate severity as a variable. Reaction severity, particularly following accidental exposure, depends on multiple factors, related to the allergen, the host and any treatments, which might be administered. Some of these factors are plausibly still unknown. Quantitative risk assessment shows that limiting exposure through control of dose reduces the rates of reactions in allergic populations, but its impact on the relative frequency of severe reactions at different doses is unclear. Food challenge studies suggest that the relationship between dose of allergenic food and reaction severity is complex even under relatively controlled conditions. Because of these complexities, epidemiological studies provide very limited insight into this aspect of the dose-response relationship. Emerging data from single-dose challenges suggest that graded food challenges may overestimate the rate of severe reactions. It may be necessary to generate new data (such as those from single-dose challenges) to reliably identify the effect of dose on severity for use in QRA. Success will reduce uncertainty in the susceptible population and improve consumer choice.

Derivation of Occupational Thresholds of Toxicological Concern for Systemically Acting Noncarcinogenic Organic Chemicals

Many substances in workplace do not have occupational exposure limits. The threshold of toxicological concern (TTC) principle is part of the hierarchy of approaches useful in occupational health risk assessment. The aim of this study was to derive occupational TTCs (OTTCs) reflecting the airborne concentrations below which no significant risk to workers would be anticipated. A reference dataset consisting of the 8-h threshold limit values-Time-Weighted Average for 280 organic substances was compiled. Each substance was classified into low (class I), intermediate (class II), or high (class III) hazard categories as per Cramer rules. For each chemical, n-octanol:water partition coefficient and vapor pressure along with the molecular weight were used to predict the blood:air partition coefficient. The blood:air partition coefficient along with data on water solubility and ventilation rate allowed the prediction of pulmonary retention factor and absorbed dose in workers. For each Cramer class, the distribution of the predicted doses was analyzed to identify the various percentile values corresponding to the OTTC. Accordingly, for Cramer classes I-III, the OTTCs derived in this study correspond to 0.15, 0.0085, and 0.006 mmol/d, respectively, at the 10th percentile level, while these values were 1.5, 0.09 and 0.03 mmol/d at the 25th percentile level. The proposed OTTCs are not meant to replace the traditional occupational exposure limits, but can be used in data-poor situations along with exposure estimates to support screening level risk assessment and prioritization.

Derivation of an inhalation TTC for the workplace based on DNEL values reported under REACH

The Threshold of Toxicological Concern (TTC) concept defines a generic tolerable exposure for chemicals of unknown toxicity below which the risk of adverse health effects is considered very small. The original concept was refined and extended over the years, based either on differentiated structural classes or on additional information on certain toxicological endpoints. Initially, the focus of the TTC application was only on systemic toxic effects after repeated oral intake and consisted of one value. However, under well-defined boundary conditions, a long-term systemic inhalation TTC could also serve as a cut-off criterion for occupational exposure in those cases where workers are exposed to very low levels of chemicals by inhalation contact and could therefore reduce the need to perform animal tests. Within the scope of the European REACH legislation, several thousand systemic long-term inhalation Derived No Effect Levels (DNELs) for workers have been published. By statistical evaluation of the DNEL distribution of 1876 chemicals and the resulting 99th percentiles, we propose an inhalation workplace TTC for systemic effects in the region of 50 μg/m³ (7 μg/kg body weight/day). Specific exclusion criteria apply for the discussed concept.

Decision support for water quality management of contaminants of emerging concern

Water authorities and drinking water companies are challenged with the question if, where and how to abate contaminants of emerging concern in the urban water cycle. The most effective strategy under given conditions is often unclear to these stakeholders as it requires insight into several aspects of the contaminants such as sources, properties, and mitigation options. Furthermore the various parties in the urban water cycle are not always aware of each other's requirements and priorities. Processes to set priorities and come to agreements are lacking, hampering the articulation and implementation of possible solutions. To support decision makers with this task, a decision support system was developed to serve as a point of departure for getting the relevant stakeholders together and finding common ground. The decision support system was iteratively developed in stages. Stakeholders were interviewed and a decision support system prototype developed. Subsequently, this prototype was evaluated by the stakeholders and adjusted accordingly. The iterative process lead to a final system focused on the management of contaminants of emerging concern within the urban water cycle, from wastewater, surface water and groundwater to drinking water, that suggests mitigation methods beyond technical solutions. Possible wastewater and drinking water treatment techniques in combination with decentralised and non-technical methods were taken into account in an integrated way. The system contains background information on contaminants of emerging concern such as physical/chemical characteristics, toxicity and legislative frameworks, water cycle entrance pathways and a database with associated possible mitigation methods. Monitoring data can be uploaded to assess environmental and human health risks in a specific water system. The developed system was received with great interest by potential users, and implemented in an international water cycle network.

Hormesis in precautionary regulatory culture: models preferences and the advancement of science

The article focuses on flaws in the actual approaches of exposure to a chemical of recipient organisms. It demonstrates the excessive use of arguments based on adverse effects and underlines the necessity to take adaptive effects seriously. Regulators are invited to rethink their inclination to the `When in doubt, keep it out.' precautionary approach, with results in counter-productive and costly regulations. The authors are clear about the necessity to include hormesis, in the form of a toxicological insignificant exposure (TIE) level, related to the concentration, as a regulatory translation of adaptive effects. This inclusion might well be the `brake' for the looming `collision' with reality of the actual linear toxicological models. This analysis includes the advice to EPA, not to follow the `witch hunt of synthetic chemicals' as embodied in the EU REACH program. Human & Experimental Toxicology (2007) 26, 855 — 873

Stochastic developmental variation, an epigenetic source of phenotypic diversity with far-reaching biological consequences

This article reviews the production of different phenotypes from the same genotype in the same environment by stochastic cellular events, nonlinear mechanisms during patterning and morphogenesis, and probabilistic self-reinforcing circuitries in the adult life. These aspects of phenotypic variation are summarized under the term 'stochastic developmental variation' (SDV) in the following. In the past, SDV has been viewed primarily as a nuisance, impairing laboratory experiments, pharmaceutical testing, and true-to-type breeding. This article also emphasizes the positive biological effects of SDV and discusses implications for genotype-to-phenotype mapping, biological individuation, ecology, evolution, and applied biology. There is strong evidence from experiments with genetically identical organisms performed in narrowly standardized laboratory set-ups that SDV is a source of phenotypic variation in its own right aside from genetic variation and environmental variation. It is obviously mediated by molecular and higher-order epigenetic mechanisms. Comparison of SDV in animals, plants, fungi, protists, bacteria, archaeans, and viruses suggests that it is a ubiquitous and phylogenetically old phenomenon. In animals, it is usually smallest for morphometric traits and highest for life history traits and behaviour. SDV is thought to contribute to phenotypic diversity in all populations but is particularly relevant for asexually reproducing and genetically impoverished populations, where it generates individuality despite genetic uniformity. In each generation, SDV produces a range of phenotypes around a well-adapted target phenotype, which is interpreted as a bet-hedging strategy to cope with the unpredictability of dynamic environments. At least some manifestations of SDV are heritable, adaptable, selectable, and evolvable, and therefore, SDV may be seen as a hitherto overlooked evolution factor. SDV is also relevant for husbandry, agriculture, and medicine because most pathogens are asexuals that exploit this third source of phenotypic variation to modify infectivity and resistance to antibiotics. Since SDV affects all types of organisms and almost all aspects of life, it urgently requires more intense research and a better integration into biological thinking.

Pesticide residues in some herbs growing in agricultural areas in Poland

The aim of this paper was to assess residue content of plant protection products in selected herbs: Achillea millefolium L., Cichorium intybus L., Equisetum arvense L., Polygonum persicaria L., Plantago lanceolata L., and Plantago major L. The study comprises herbs growing in their natural habitat, 1 and 10 m away from crop fields. The herbs, 30 plants of each species, were sampled during the flowering stage between 1 and 20 July 2014. Pesticide residue content was measured with the QuECHERS method in the dry matter of leaves, stalks, and inflorescence, all mixed together. Out of six herb species growing close to wheat and maize fields, pesticide residues were found in three species: A. millefolium L., E. arvense L., and P. lanceolata L. Most plants containing the residues grew 1 m away from the wheat field. Two active substances of fungicides were found: diphenylamine and tebuconazole, and one active substance of insecticides: chlorpyrifos-ethyl. Those substances are illegal to use on herbal plants. Samples of E. arvense L. and P. lanceolata L. contained two active substances each, which constituted 10% of all samples, while A. millefolium L. contained one substance, which is 6.6% of all samples.

Pesticide residues in cereal crop grains in Poland in 2013

This paper presents the results of the audit on pesticide residues in cereal grains throughout Poland in 2013. The number of all samples of cereal grains was 380. Altogether 292 active substances of plant protection products were checked in the audit. Qualitative and quantative analyses were done according to Polish Standard PN-EN 15562:2008, using the LC-MS/MS technique. The methods (QuEChERS) is based on extraction of residues of plant protection products from a sample using acetonitrile. In the samples analyzed, 62 % of them did not contain any pesticide residues, 34 % of samples of cereal grains contained such residues but below the maximum residue limit, 3 % contained residues over the maximum limit, whereas 1 % of the samples contained illegal substances. The lowest amounts of pesticide residues were found in cereal grains coming from fields with cereal mixtures and in Avena grains, while the highest amounts were in Hordeum and Triticum grains. The substances found most often were fungicide residues. In northern and southern regions of Poland (Silesian, Pomeranian, and Kuyavian-Pomeranian voivodeships), cereal grains with pesticide residues were much more common than in other regions of Poland.