Karyne M Rogers

• PhD
• Senior Researcher at GNS Science

Nitrate data quality is comparatively analysed using a standard ring test. Data produced by commercial laboratories are compared with portable testing instruments.

Background: Alcoholic beverages have been popular for thousands of years due to their unique flavors and cultural significance. However, the industry’s high profit margins have led to increasingly sophisticated counterfeiting practices. Stable isotope analysis has emerged as one of the most promising techniques for addressing authenticity and trace...

China is the world’s largest consumer and second largest producer of bananas. This strong domestic demand consistently provides a reliable income for Chinese banana growers. The geographical origin of food is usually associated with product quality and safety, and this is especially noted for Hainan origin-labeled bananas, which are grown offshore...

The nutritional quality of bananas and their geographical origin authenticity are very important for trade. There is an urgent need for rapid, non-destructive testing to improve the origin and quality assurance for importers, distributors, and consumers. In this study, 99 banana samples from a range of producing countries were collected. Hyperspect...

Rheum tanguticum is one of the primary rhubarb species used for food and medicinal purposes, and it has recently been gaining more attention and recognition. This research represents the first attempt to use stable isotopes and elemental analysis via IRMS to identify the geographical origin of Rheum tanguticum. A grand total of 190 rhubarb samples...

Verification of cowpea geographical origin has become more critical in recent times to guarantee food safety and enhance government management of potentially hazardous pesticide farming practices. Cowpea samples harvested in five major southern provinces in China were characterized by stable isotopes (δ¹³C, δ¹⁵N, δ²H, δ¹⁸O) and elemental contents (...

Groundwater denitrification studies require the careful quantification of excess N2 to determine that nitrate reduction has taken place. The measurement of corresponding noble gases Ne and Ar quantifies excess air N2 and in situ degassing. We compare, for the first time, measurement results from a high-precision quadrupole mass spectrometer (QMS) w...

The Ministry for the Environment and Ministry of Education commissioned GNS Science (GNS) to coordinate and report on the first nationwide groundwater quality testing programme of rural school drinking-water supplies. Declining groundwater quality has been reported across rural New Zealand, with specific concerns around increasing nitrate levels du...

Effective geographical origin discrimination of Chinese rice requires a large database of samples to ensure sufficient data for origin verification at a regional scale. In this study, environmental similarity was used to establish a spatial database of rice nutrient element, and then the validity of the database was verified using the back propagat...

The nitrogen-stable isotopes of plants can be used to verify the source of fertilizers, but the fertilizer uptake patterns in tea (Camellia sinensis) plants are unclear. In this study, potted tea plants were treated with three types of organic fertilizers (OFs), urea, and a control. The tea leaves were sampled over seven months from the top, middle...

Seasonal (temporal) variations can influence the δ¹³C, δ²H, δ¹⁸O, and δ¹⁵N values and nutrient composition of organic (ORG), green (GRE), and conventional (CON) vegetables with a short growth cycle. Stable isotope ratio mass spectrometry (IRMS) and near-infrared spectroscopy (NIRS) combined with the partial least squares-discriminant analysis (PLS-...

Light stable isotopes ( δ ¹³ C, δ ¹⁵ N, δ ² H, and δ ¹⁸ O) of Ectropis grisescens (a leaf-eating pest) were measured at different developmental stages. Isotope values of larval instars, pupae, and adult tissues were determined to understand fractionation patterns at different life stages and to evaluate the tropic shift from food to insect to excre...

Grapes are an important seasonal fresh fruit in China, and their quality and nutrition is closely linked to their geographical origin. Stable isotopes and elemental profiles of grapes and corresponding soils from different regions and harvest years were determined using isotope ratio mass spectrometry (IRMS) and inductively coupled plasma mass spec...

1. No denitrification was detected in untreated bore water after 4 weeks under varying temperature and light treatments 2. Changes in nitrate concentration were less than potential instrument error 3. Denitrification is unlikely to be a major source of error in this mail-in nitrate testing programme 4. We encourage replication with more sensitive i...

Verifying the geographical origin of soybeans (Glycine max [Linn.] Merr.) is a major challenge as there is little available information regarding non-parametric statistical origin approaches for Chinese domestic and imported soybeans. Commercially procured soybean samples from China (n = 33) and soybeans imported from Brazil (n = 90), the United St...

A study of different grapevine tissues and organs (root, stem, leaf, fruit) water isotope fractionation models from high-quality wine grapes produced in the Helan Mountains, a key wine-producing area in northwestern China, was undertaken. Results showed that δ2H values of local groundwater sources were more negative than rivers and precipitation. S...

A geochemical atlas for Aotearoa New Zealand is presented that highlights the variation in trace element concentrations in near-surface soil materials across Te Ika-a-Maui North Island, Te Waipounamu South Island and Rakiura Stewart Island. Samples were sourced from previous studies, collated from 833 sites from the top 30 cm (maximum) of soil by h...

Isotope ratio mass spectrometry (IRMS) combined with multivariate analysis was employed to develop a new quality control tool for Chinese Ganoderma lucidum. The effect of growth stage, substrate, cultivar type and geographical origin on the elemental and isotopic compositions was investigated. Stable isotopes (δ13C, δ15N, and δ18O) and elemental co...

This review compiles publicly available datasets describing the chemical composition of geothermal fluids from eight wells in the Taupo Volcanic Zone (TVZ) and Ngāwhā, New Zealand. Our review allows previously reported geothermal reservoir water compositions at various locations around the TVZ (and Ngāwhā) to be assessed and compared for the first...

Chrysanthemum morifolium Ramat., known as Hangbaiju (HBJ), is a high-value edible, medicinal product where the flowers are infused in hot water and drunk as tea. Its quality and efficacy are closely related to its geographical origin. Consequently, it is vulnerable to fraudulent substitution by other lower-value Chrysanthemum products. In this stud...

The effect of fertilizer supply and light intensity on the distribution of elemental contents (%C and %N) and light stable isotopes (C, N, H, and O) in different rice fractions (rice husk, brown rice, and polished rice) of two hybrid rice cultivars (maintainer lines You-1B and Zhong-9B) were investigated. Significant variations were observed for δ¹...

Augustus Hamilton (1853-1913) was a New Zealand ethnologist and naturalist who amassed a significant collection of fossils, mostly of birds, during his career. Today, those fossils are housed in the Museum of New Zealand Te Papa Tongarewa (NMNZ). While some fossils have been catalogued and integrated into the collection of the NMNZ, a large part re...

A national survey identifies the extent and origin of nitrates in New Zealand’s freshwater resources using ni�trogen (δ15N) and oxygen (δ18O) isotopes. A comprehensive database with 1042 samples investigates freshwater type, land-use, geology, soil type and geographic effects on nitrate isotopes across New Zealand. Nitrate contamination is the bi...

Compound-specific stable isotope analysis (CSIA) of food products is a relatively new and novel technique used to authenticate food and detect adulteration. This paper provides a review of recent on-line and off-line CSIA applications of plant and animal origin foods, essential oils and plant extracts. Different food discrimination techniques, appl...

Over the last decade, isotope ratio mass spectrometry (IRMS) using up to 5 light stable isotopes (13C/12C, 2H/1H, 15N/14N, 18O/16O, 34S/32S) has become more widely applied for food origin verification as well as food authentication in China. IRMS technology is increasingly used to authenticate a range of food products including organic foods, honey...

A comprehensive study of 96 bottled mineral water (BMW) samples consisting of 21 of the most popular origins and brands sourced from China (n = 38), France (n = 20), Italy (n = 10), New Zealand (n = 17) and Fiji (n = 12) has been undertaken. The δ18O and δ13C of dissolved inorganic carbon (DIC), δ18O and δ2H of water, mineral elements (Li, Na, Mg,...

Stable hydrogen, carbon, nitrogen, oxygen and sulfur (HCNOS) isotope compositions expressed as isotope-delta values are typically reported relative to international standards such as Vienna Standard Mean Ocean Water (VSMOW), Vienna Peedee belemnite (VPDB) or Vienna Cañon Diablo Troilite (VCDT). These international standards are chosen by convention...

Origin verification of high-value saffron is essential for fair trade and to protect consumers' interests and rights. A traceability method using elemental content (% C and % N) and stable isotopes (δ¹³C, δ²H, δ¹⁸O, and δ¹⁵N) combined with chemometrics was developed to discriminate saffron from Iran and China and classify major domestic production...

Soil chemistry is driven by environmental conditions, parent material and the rate and type of anthropogenic input. Cities built on soil derived from volcanic rock make up a rare yet important subset of urban areas globally. Here we conducted an urban geochemical baseline survey over Auckland, New Zealand's most populous city, built over several vo...

This study investigates the use of stable isotopes (C, N, H, and O) to characterize the geographical origin of peanuts along with different peanut fractions including whole peanut kernel, peanut shell, delipidized peanuts and peanut oil. Peanut samples were procured in 2017 from three distinctive growing regions (Shandong, Jilin, and Jiangsu) in Ch...

The authentication of geographical origin of food is important using stable isotope analysis. However, the isotopic databank is still short of comprehensive. The isoscapes model based on environmental similarity is used for the first time to predict the geospatial distribution of δ¹³C, δ²H and δ¹⁸O in Chinese rice in 2017 and 2018. 794 rice samples...

Geographical origin discrimination of agro-products is essential to guarantee food safety and fair trade. Garlic samples cultivated in six provinces or major production regions in China were characterized for stable isotopes (δ13C, δ2H, δ18O, δ15N, and δ34S), bioelemental contents (% C, % N and % S), and sulfur-containing compounds (8 organosulfur...

A regional soil study of 61 sites from the Wairau and Awatere Valleys, Marlborough region, New Zealand characterised the geochemical baselines of different land-use types. The study used three stable isotopes (δ¹³C, δ¹⁵N, δ³⁴S) and 65 elements to describe the influence of parent-rock geology, human and climate-induced effects and natural transport...

Songjiang CPB rice (cultivated by a ‘combination of planting and breeding’) and Chongming NCFP rice (cultivated by using ‘no chemical fertilizers and pesticides’) are two high quality special rice products developed for Shanghai urban agriculture. Protecting these products from geographical origin mislabeling or cultivation method fraud are very im...

The authenticity of rice has become an important issue over the last few years. Many techniques have been employed in rice authentication including geographical origin, cultivar discrimination, organic rice authenticity, and impurities detection in rice. This review paper is attempted to highlight the current literature (past twenty years) on the d...

This review compiles and presents a publicly available database on the chemical composition of geothermal waters from wells and springs in the Taupo Volcanic Zone (TVZ) and Ngawha, New Zealand. The purpose of this review is to collate previously dispersed datasets, to enable the typical geothermal reservoir water compositions at various locations a...

When ecosystems are under severe pressure or environments change, trophic position and intraspecific niche width may decrease or narrow, signalling that conservation action is required. In New Zealand, alpine and subalpine ecosystems have been extensively modified through farming since 19th‐century European settlement, with consequences for indigen...

Rice is an important staple food in China, which authenticity is closely associated with nutrition and safety. It is necessary to discriminate their geographical origin with a comprehensive databank. 900 Japonica and Indica rice samples from 17 provinces were collected to analysis stable isotopes and trace elements for their origin discrimination o...

As people, animals and materials are transported across increasingly large distances in a globalized world, threats to our biosecurity and food security are rising. Aotearoa New Zealand is an island nation with many endemic species, a strong local agricultural industry, and a need to protect these from pest threats, as well as the economy from frau...

Stable isotopes (δ²H, δ¹³C, δ¹⁵N and δ¹⁸O) of 232 milk powders and 88 fresh milk samples collected globally were used to distinguish fresh milk from reconstituted milk and qualitatively detect extraneous nitrogen in milk products. Nitrogen isotopes of six nitrogen-containing milk additives, including animal protein (peptone), soy protein, and four...

Rice quality is directly related to human health, so it is important to have traceability systems that can trace inferior or contaminated rice back to its geographical origin. This ensures farming practices in substandard regions become better regulated to improve rice quality, origin labelling and consumer trust. However, tracing the origin of ric...

Not-from-concentrate (NFC) juice has better nutrition, flavor and higher price than reconstituted juice. Accordingly, NFC juice is prone to adulteration and is an ongoing industry problem that has not yet been resolved. Undeclared addition of water and sugar are the main forms of NFC juice adulteration. This paper investigates the carbon and oxygen...

Not-from-concentrate (NFC) juice has better nutrition, flavor and higher price than reconstituted juice. Accordingly, NFC juice is prone to adulteration and is an ongoing industry problem that has not yet been resolved. Undeclared addition of water and sugar are the main forms of NFC juice adulteration. This paper investigates the carbon and oxygen...

Xinjiang muskmelon is a popular fruit in China that is exported worldwide. In particular, Hami muskmelon is classified as a protected geographical indication (PGI) product, and consequently it is more desirable and sells at a higher market price than products from other regions. Origin mislabeling and fraudulent substitution of Hami PGI muskmelon p...

The stable isotope and photosynthesis response of tea (Camellia sinensis) is determined under different light and temperature conditions. The results showed that isotopes of young tea leaves were more enriched with increasing light intensity (31∼411 µmol m⁻²∙s⁻¹). However, the value of δ¹³C and δ¹⁵N seemed depleted, while δ²H and δ¹⁸O became enrich...

ARTICLE INFO Keywords: Infa nt formu la Fr esh mi lk Stable is otopes Geogr ap hical or igi n Discrim ina nt an al ysi s ANN ABSTRACT China is the largest importer of infant formu la. However, monitoring the authenticity of infant formu la has long be en a problem in China. The origin of infant formu la is more difficu lt to trace than fresh milk b...

The Chatham Island Duck, Anas chathamica, is one of many New Zealand bird species that became extinct after Polynesian arrival. The Chatham Island Duck was a large flightless bird, with salt glands on its skull, which led to the hypothesis that it lived in a marine habitat. We tested this hypothesis using a combination of stable isotope analysis (c...

Indonesian coconut sugar (n = 109 samples) from different local producers was analyzed over a 2-year period. A mean δ13C value of − 25.6‰ ± 0.4‰ was determined for unadulterated (pure) coconut sugar. Seasonal climatic differences of up to ± 0.4‰ increase the standard deviations of coconut sugar (− 25.6‰ ± 0.8‰). Up to 5% w/v of cane sugar is often...

China is the largest importer of infant formula. However, monitoring the authenticity of infant formula has long been a problem in China. The origin of infant formula is more difficult to trace than fresh milk because it contains many foreign additives that cannot be correlated to a specific country. In this study, stable isotope ratios (δ¹⁵N, δ¹³C...

Determining the geographical origin of specialty fruits imported into China is important to protect the legitimate rights and interests of consumers against mislabeled origin fruits and may provide a regulatory tool to verify fruit sold into international markets. This study aims to establish an accurate and effective method to identify the geograp...

Jinxiang garlic is a well-known commodity with protected geographical indication (PGI) status in China and is also registered PGI in the European Union. A stable isotope profile (¹³C, ¹⁵N, ²H, ¹⁸O, and ³⁴S) was used to construct a discrimination model to differentiate PGI Jinxiang garlic from other major garlic export countries (Argentina and South...

Low-yielding early-spring (ES) Longjing tea is popular with Chinese consumers and commands a high price due to its scarcity, but it has a heightened risk of substitution with lower value tea products from later harvest periods due to similarities in appearance. In this study, tea samples from different harvest periods were analyzed using stable iso...

Rationale A combination of stable carbon (δ¹³C) and hydrogen (δ²H) isotope ratios and carbon content (% C) was evaluated as a rapid, low‐cost analytical approach to authenticate bioplastics, complementing existing radiocarbon (¹⁴C) and Fourier transform infrared (FTIR) analytical methods. Methods Petroleum‐ and bio‐based precursor materials and in...

Shanghai city has encountered possible food fraud regarding the geographical mislabeling of vegetables for economic gain. A combination of δ¹³C, δ¹⁵N, δ²H and δ¹⁸O values and partial least squares discrimination analysis and support vector machine (SVM) methods were used for the first time to assess farming methods and determine the origin of veget...

Origin verification of 240 French wines from four regions of France was undertaken using isotope and elemental analyses. Our aim was to identify and differentiate the geographical origin of these red wines, and more importantly, to build a classification tool that can be used to verify geographic origin of French red wines using machine learning mo...

Jujube is widely grown in Xinjiang province, China, including two high-value PGI products, Charkhlik Hui jujube and Khotan Jun jujube. Origin mislabeling and substitution of PGI jujube by inferior products seriously harms their reputation and has potential food safety risks. In this study, stable isotope (δ¹³C, δ¹⁵N, δ²H, δ¹⁸O) and elemental (Na, M...

Stable carbon (δ¹³C) and nitrogen (δ¹⁵N) isotope ratios and multi-element signatures of pooled fish scales were used to differentiate wild, lake-farmed and pond-farmed carp from Dongting Lake, China. Fish scales were found to be important archives for the dietary history and trophic level of wild and farmed fish, indicating their food sources. δ¹³C...

High-value yak meat from Qinghai-Tibet Plateau was investigated using stable isotopes (δ¹³C, δ²H, δ¹⁸O, δ¹⁵N and δ³⁴S) to identify attributes which could verify and protect its geographical origin. Supervised PLS-DA was applied to the isotope data to discriminate four geographical locations. δ¹³C, δ²H, and δ¹⁸O values showed significant differences...

Incidents of fraud are emerging on the domestic Chinese honey market, especially where lower value rape honey is mixed with high-value acacia honey. In this study, we use a combination of ¹H NMR spectroscopy combined with chemometric techniques to detect and quantify adulteration of acacia honey with cheaper rape honey. The honey ¹H NMR spectroscop...

As far as we known, recent studies on the origin of agricultural products rarely focus on the source of cities or counties even small-scale districts, but traceability of small-scale districts of food is the research trend and difficulty of future researches. The most commonly used methods of origin tracing researches are stable isotope and element...

Organically farmed rice is believed to be healthier, safer and eco-friendlier than its conventionally farmed counter-part and sells for a premium price in global markets. Deliberate mislabeling of organic rice has become a critical consumer concern in China and elsewhere, and there is increased risk of buying fraudulent organic rice in the market p...

Cow milk samples from various provinces in China were collected, and the effects of lactation stage, sampling time, and geographic origin on the samples were studied by elemental analysis-isotope ratio mass spectrometry (EA-IRMS). Traceability accuracy was determined using δ13C, δ15N, δ2H and δ18O values to specifically assign geographic origin. St...

Breeding in most species is timed to coincide with the greatest availability of food resources to support the increased energetic needs of reproduction. Correspondingly, the majority (76%) of seabird species in temperate and polar regions breed in spring/summer, matching the peak in ocean productivity. The Fiordland penguin Eudyptes pachyrhynchus i...

Rationale Deliberate and fraudulent origin mislabeling of Chinese green tea motivated by large price differences often brings significant food safety risks and damages consumer trust. Currently, there is no reliable method to verify the origin of green tea produced in China. Stable isotope and multi‐element analyses combined with statistical models...

Rationale Isotope reference materials are essential to enable reliable and comparable isotope data across multiple laboratories. Although many reference materials already exist, the best reference materials should mimic the unknown samples, so new reference materials continue to evolve with the development of isotope research in new product areas....

Chinese wolfberry or goji berry (Lycium barbarum) is an important traditional Chinese medicine. Its price and function has a close correlation with its geographical provenance. Illegal mislabeling motivated by commercial gains brings serious food safety problems and damages consumer confidence. In this work, a novel analytical strategy combined wit...