Thermoultrasonication, ultraviolet-C irradiation, and high-pressure processing: Novel techniques to preserve insulin in donor human milk.

BACKGROUND & AIMS: Donor human milk (DHM) is recommended as the first alternative for preterm infants if their mother's own milk is not available or if the quantity is not sufficient. The most commonly used technique to eliminate microbial contaminants in DHM is holder pasteurization (HoP). However, the heating process during HoP partially destroys milk bioactive factors such as insulin. Therefore, innovative techniques have been developed as alternatives to HoP. The objective of this study was to determine the effect of HoP, high-temperature-short-time (HTST), thermoultrasonication (TUS), ultraviolet-C irradiation (UV-C), and high-pressure processing (HPP) on the insulin concentration in DHM. METHODS: Milk samples from 28 non-diabetic mothers were collected. The milk samples were aliquoted and either left untreated or treated with HoP (62.5 °C; 30 min), HTST (72 °C; 15 s), TUS (60 W; 6 min), UV-C (4863 J/L), or HPP (500 MPa; 5 min). RESULTS: The mean insulin concentration in untreated milk was 79 ± 41 pmol/L. The mean insulin retention rate was 67% for HoP, 78% for HTST, 97% for TUS, 94% for UV-C, and 106% for HPP. The mean insulin concentration in milk treated with HoP was significantly lower compared to untreated milk (p = 0.01). CONCLUSION: TUS, UV-C, and HPP preserve insulin in DHM. The insulin concentration in DHM is affected to a larger extent by HoP than by HTST. These results indicate that TUS, UV-C, and HPP may serve as alternatives to HoP.

Staphylococcus aureus Enterotoxin Production in Raw, Holder-Pasteurized, and Ultraviolet-C-Treated Donated Human Milk.

Background: Some strains of Staphylococcus aureus can produce heat-stable enterotoxins that have been associated with gastritis and potentially necrotizing enterocolitis in preterm infants. Objectives/Hypothesis: To assess the impact of different storage temperatures on S. aureus growth and enterotoxin production in raw, Holder-pasteurized (HP) and ultraviolet-C (UV-C)-treated donated human milk (DHM). Materials and Methods: The milk samples from individual donors were pooled and divided into four equal portions. One portion was HP, the second was UV-C treated, the third was not treated, and the fourth was UV-C treated after being spiked with S. aureus. All samples were incubated at 37°C (18 hours) and 4°C (14 days). Bacterial colony count, enterotoxin A and B, and immune proteins were quantified. Results: At 37°C, the colony count increased in HP DHM and decreased in raw and UV-C-treated DHM. At 4°C, colony counts in HP DHM reduced and were not detected in raw and UV-C-treated DHM from day 8 of incubation. No bacteria were detected in samples that were inoculated before UV-C treatment. Enterotoxin A was only detected in HP-DHM at 37°C from the 9th hour onward. Enterotoxin B was detected in one sample at the 15th hour. Immune protein concentrations were similar in raw and UV-C DHM, and were reduced in the HP DHM. Conclusion: UV-C-treated milk reduces S. aureus growth with similar kinetics to raw milk making it a promising emerging technique to eliminate bacteria while retaining essential immune proteins in DHM.

The consequence of phototherapy exposure on oxidative stress status of expressed human milk.

OBJECTIVE: There exists evidence that phototherapy can disturb the oxidant/antioxidant balance in favor of oxidants. If phototherapy is continued during tube feeding in preterms, expressed human milk is subjected to phototherapy lights for about 20 min per feeding. We aimed to investigate the effects of phototherapy lights on oxidative/antioxidative status of expressed human milk. STUDY DESIGN: Milk samples of 50 healthy mothers were grouped as control and phototherapy and exposed to 20 min of day-light and phototherapy light, respectively. Total antioxidant capacity (mmol-Trolox equiv/L) and total oxidant status (mmol-H2O2/L) in expressed human milk samples were measured. RESULTS: Levels of antioxidant capacity of the expressed human milks in the phototherapy group were lower than those of the control group [mmol-Trolox equiv/L; median (interquartile-range): 1.30 (0.89-1.65) and 1.77 (1.51-2.06), p: < .001]. Levels of oxidant status were similar in both groups. CONCLUSION: We demonstrated that phototherapy decreased antioxidant capacity of expressed human milk without any alteration in oxidative status. We think that this observation is important for the care of very low birth weighted infants who have limited antioxidant capacity and are vulnerable to oxidative stress. It may be advisable either to turn off the phototherapy or cover the tube and syringe to preserve antioxidant capacity of human milk during simultaneous tube feeding and phototherapy treatment.

Pasteurization Procedures for Donor Human Milk Affect Body Growth, Intestinal Structure, and Resistance against Bacterial Infections in Preterm Pigs.

Background: Holder pasteurization (HP) destroys multiple bioactive factors in donor human milk (DM), and UV-C irradiation (UVC) is potentially a gentler method for pasteurizing DM for preterm infants.Objective: We investigated whether UVC-treated DM improves gut maturation and resistance toward bacterial infections relative to HP-treated DM.Methods: Bacteria, selected bioactive components, and markers of antioxidant capacity were measured in unpasteurized donor milk (UP), HP-treated milk, and UVC-treated milk (all from the same DM pool). Fifty-seven cesarean-delivered preterm pigs (91% gestation; ratio of males to females, 30:27) received decreasing volumes of parental nutrition (average 69 mL · kg-1 · d-1) and increasing volumes of the 3 DM diets (n = 19 each, average 89 mL · kg-1 · d-1) for 8-9 d. Body growth, gut structure and function, and systemic bacterial infection were evaluated.Results: A high bacterial load in the UP (6×105 colony forming units/mL) was eliminated similarly by HP and UVC treatments. Relative to HP-treated milk, both UVC-treated milk and UP showed greater activities of lipase and alkaline phosphatase and concentrations of lactoferrin, secretory immunoglobulin A, xanthine dehydrogenase, and some antioxidant markers (all P < 0.05). The pigs fed UVC-treated milk and pigs fed UP showed higher relative weight gain than pigs fed HP-treated milk (5.4% and 3.5%), and fewer pigs fed UVC-treated milk had positive bacterial cultures in the bone marrow (28%) than pigs fed HP-treated milk (68%) (P < 0.05). Intestinal health was also improved in pigs fed UVC-treated milk compared with those fed HP-treated milk as indicated by a higher plasma citrulline concentration (36%) and villus height (38%) (P < 0.05) and a tendency for higher aminopeptidase N (48%) and claudin-4 (26%) concentrations in the distal intestine (P < 0.08). The gut microbiota composition was similar among groups except for greater proportions of Enterococcus in pigs fed UVC-treated milk than in pigs fed UP and those fed HP-treated milk in both cecum contents (20% and 10%) and distal intestinal mucosa (24% and 20%) (all P < 0.05).Conclusions: UVC is better than HP treatment in preserving bioactive factors in DM. UVC-treated milk may induce better weight gain, intestinal health, and resistance against bacterial infections as shown in preterm pigs as a model for DM-fed preterm infants.

The effect of simulated flash heating pasteurisation and Holder pasteurisation on human milk oligosaccharides.

BACKGROUND: Human milk oligosaccharides (HMOs) have important protective functions in human milk. A low-cost remote pasteurisation temperature-monitoring system has been designed using FoneAstra, a cell phone-based networked sensing system to monitor simulated flash heat pasteurisation. AIM: To compare the pasteurisation effect on HMOs of the FoneAstra FH method with the current Sterifeed Holder method used by human milk banks. METHODS: Donor human milk samples (n = 48) were obtained from a human milk bank and pasteurised using the two pasteurisation methods. HMOs were purified from samples and labelled before separation using high-performance liquid chromatography. Concentrations of total HMOs, sialylated and fucosylated HMOs and individual HMOs using the two pasteurisation methods were compared using repeated-measures ANOVA. RESULTS: The study demonstrated no difference in total concentration of HMOs between the two pasteurisation methods and a small but significant increase in the total concentration of HMOs regardless of pasteurisation methods compared with controls (unpasteurised samples) (p<0.0001). CONCLUSION: The FoneAstra FH pasteurisation system does not negatively affect oligosaccharides in human milk and therefore is a possible alternative for providing safely sterilised human milk for low- and middle-income countries.

Inactivation of Cytomegalovirus in Breast Milk Using Ultraviolet-C Irradiation: Opportunities for a New Treatment Option in Breast Milk Banking.

Pasteurized donor human milk is provided by milk banks to very preterm babies where their maternal supply is insufficient or unavailable. Donor milk is currently processed by Holder pasteurization, producing a microbiologically safe product but significantly reducing immunoprotective components. Ultraviolet-C (UV-C) irradiation at 254 nm is being investigated as an alternative treatment method and has been shown to preserve components such as lactoferrin, lysozyme and secretory IgA considerably better than Holder pasteurization. We describe the inactivation of cytomegalovirus, a virus commonly excreted into breast milk, using UV-C irradiation. Full replication was ablated by various treatment doses. However, evidence of viral immediate early proteins within the cells was never completely eliminated indicating that some viral gene transcription was still occurring. In conclusion, UV-C may be a safe alternative to pasteurisation for the treatment of human donor milk that preserves the bioactivity. However, our data suggests that CMV inactivation will have to be carefully evaluated for each device designed to treat breast milk using UV-C irradiation.

68Ga-DOTATATE Breast Uptake and Expression in Breast Milk.

The excretion of Ga-DOTA-Octreotate (DOTATATE) and related somatostatin analogues in breast milk has not been demonstrated. We report a case of a 34-year-old woman, 7 months postpartum and breastfeeding, who was referred for DOTATATE imaging after the diagnosis of appendiceal carcinoid and subsequent appendectomy. Prominent breast uptake was noted. A breast milk sample from the patient at 90 minutes postinjection was assayed in a gamma counter and shown to have a concentration of 5.6 Bq/g per MBq administered. The excretion of DOTATATE in breast milk is important to consider when providing radiation safety advice to breastfeeding patients.

Excretion of radionuclides in human breast milk after nuclear medicine examinations. Biokinetic and dosimetric data and recommendations on breastfeeding interruption.

PURPOSE: To review early recommendations and propose guidelines for breastfeeding interruption after administration of radiopharmaceuticals, based on additional biokinetic and dosimetric data. METHODS: Activity concentrations in breast milk from 53 breastfeeding patients were determined. The milk was collected at various times after administration of 16 different radiopharmaceuticals. The fraction of the activity administered to the mother excreted in the breast milk, the absorbed doses to various organs and tissues and the effective dose to the infant were estimated. RESULTS: The fraction of the administered activity excreted per millilitre of milk varied widely from 10(-10) to 10(-3) MBq/MBq administered. For (99m)Tc-labelled radiopharmaceuticals, the total fraction of the administered activity excreted in the milk varied from 0.0057 % for (99m)Tc-labelled red blood cells (RBC) to 19 % for (99m)Tc-pertechnetate. The effective dose to an infant per unit activity administered to the mother ranged from 6.7 × 10(-6) mSv/MBq for (99m)Tc-labelled RBC to 3.6 × 10(-2) mSv/MBq for (99m)Tc-pertechnetate. For the other radiopharmaceuticals, the total fraction of administered activity excreted in the milk varied from 0.018 % ((51)Cr-EDTA) to 48 % ((131)I-NaI). The effective dose ranged from 5.6 × 10(-5) mSvinfant/MBqmother ((51)Cr-EDTA) to 106 mSvinfant/MBqmother ((131)I-NaI). CONCLUSIONS: Based on an effective dose limit of 1 mSv to the infant and a typical administered activity, we recommend cessation of breastfeeding for (131)I-NaI and interruption of feeding for 12 h for (125)I-iodohippurate, (131)I-iodohippurate, (99m)Tc-pertechnetate and (99m)Tc-MAA. During this 12-h period all breast milk should be expressed at least three times and discarded. For the other radiopharmaceuticals included in this study, no interruption of breastfeeding is necessary.

Milk supply related to childhood leukaemia treatment.

This literature review and case study answers the question: 'Do the late effects of childhood cranial radiation therapy include impacts on breastfeeding?' PubMed was searched for papers using the terms lactation and cranial radiotherapy or childhood cranial radiotherapy. The case study was written from one author's experience of helping a mother with a history of childhood cranial radiation therapy. The few available studies report a high rate of lactation failure in women who were treated with cranial radiation therapy for childhood cancer, but the exceptions indicate that lactation failure is not inevitable in this group of mothers. Breastfeeding may ameliorate some of the adverse effects of cranial radiation therapy. Health professionals caring for mothers with a history of cranial radiation therapy must balance encouraging women to breastfeed with preparing them for the possibility that they may be unable to do so.

The effect of UV-C pasteurization on bacteriostatic properties and immunological proteins of donor human milk.

BACKGROUND: Human milk possesses bacteriostatic properties, largely due to the presence of immunological proteins. Heat treatments such as Holder pasteurization reduce the concentration of immunological proteins in human milk and consequently increase the bacterial growth rate. This study investigated the bacterial growth rate and the immunological protein concentration of ultraviolet (UV-C) irradiated, Holder pasteurized and untreated human milk. METHODS: Samples (n=10) of untreated, Holder pasteurized and UV-C irradiated human milk were inoculated with E. coli and S. aureus and the growth rate over 2 hours incubation time at 37°C was observed. Additionally, the concentration of sIgA, lactoferrin and lysozyme of untreated and treated human milk was analyzed. RESULTS: The bacterial growth rate of untreated and UV-C irradiated human milk was not significantly different. The bacterial growth rate of Holder pasteurized human milk was double compared to untreated human milk (p<0.001). The retention of sIgA, lactoferrin and lysozyme after UV-C irradiation was 89%, 87%, and 75% respectively, which were higher than Holder treated with 49%, 9%, and 41% respectively. CONCLUSION: UV-C irradiation of human milk preserves significantly higher levels of immunological proteins than Holder pasteurization, resulting in bacteriostatic properties similar to those of untreated human milk.

Ultraviolet-C Irradiation: A Novel Pasteurization Method for Donor Human Milk.

BACKGROUND: Holder pasteurization (milk held at 62.5°C for 30 minutes) is the standard treatment method for donor human milk. Although this method of pasteurization is able to inactivate most bacteria, it also inactivates important bioactive components. Therefore, the objective of this study was to investigate ultraviolet irradiation as an alternative treatment method for donor human milk. METHODS: Human milk samples were inoculated with five species of bacteria and then UV-C irradiated. Untreated and treated samples were analysed for bacterial content, bile salt stimulated lipase (BSSL) activity, alkaline phosphatase (ALP) activity, and fatty acid profile. RESULTS: All five species of bacteria reacted similarly to UV-C irradiation, with higher dosages being required with increasing concentrations of total solids in the human milk sample. The decimal reduction dosage was 289±17 and 945±164 J/l for total solids of 107 and 146 g/l, respectively. No significant changes in the fatty acid profile, BSSL activity or ALP activity were observed up to the dosage required for a 5-log10 reduction of the five species of bacteria. CONCLUSION: UV-C irradiation is capable of reducing vegetative bacteria in human milk to the requirements of milk bank guidelines with no loss of BSSL and ALP activity and no change of FA.

Breast irradiation and lactation: a review.

The incidence of breast cancer in premenopausal women is increasing and many of them still remain fertile after treatment. Allied to the current tendency to postpone pregnancy, it is expected that an increasing number of patients undergoing conservative treatment for breast cancer will get pregnant. Anatomical and histopathological aspects and the probability of lactation and breast feeding after breast irradiation are reviewed in this article. Lactation is possible after radiotherapy, present in at least 50% of the patients, but in reduced volume. This perspective is more correlated to the type of surgery and radiation dose used. Biochemical changes were observed in irradiated breast milk. Breastfeeding in the contralateral breast is not affected.

Efecto del tiempo y temperatura de almacenamiento a corto plazo sobre el contenido de las proteínas en leche humana / Effects of short term storage time and temperature on the protein content of human milk

La leche materna constituye el alimento ideal para el recién nacido y el lactante en forma exclusiva hasta los 6 meses de edad; y hasta los 2 años con alimentos complementarios. El destete precoz es de causa multifactorial: falta de control prenatal, desconocimiento de los beneficios de la leche materna, hipogalactia, prácticas hospitalarias inadecuadas, publicidad de alimentos infantiles, incorporación de la madre al trabajo y como desconocimiento sobre la extracción y preservación de la leche humana. El objetivo del presente trabajo es evaluar el efecto del tiempo y temperatura de almacenamiento a corto plazo, sobre el contenido de proteínas en la leche humana madura de madres que asistieron a la consulta del Hospital “Dr. Jorge Lizárraga”, Valencia, Estado Carabobo, Venezuela. Investigación experimental, correlacional, cuantitativa y aplicada. Fueron analizadas 20 muestras de leche, de mujeres sanas, con amamantamiento en forma exclusiva, obtenidas por extracción manual. Cada una de ellas se separó en 2 la alícuotas: 1. Para analizar en fresco, 2 tras almacenamiento a 15˚C durante 24 horas. La determinación de proteínas se realiz según las normas industriales Covenin. La concentración de proteínas fue de 1,53 gr/dl en leche recién extraída y 1,50 gr/dl en leche almacenada a 15 ˚C por 24 horas. No hubo diferencia significativa entre los valores de proteínas en leche materna recién extraída y almacenada. En la leche humana almacenada a 15 ˚C durante 24 horas, las concentraciones de las proteínas no se modifican comparándola con la leche recién extraída

Maternal milk is the ideal food for newborns and infants, on an exclusive basis, up to six months and together with complementary food, up to two years of age. The early weaning could have multifactorial causes: lack of prenatal control, unawareness of the benefits of breastfeeding, hypogalactia, inappropriate hospital practices, advertising of infant foods, return of the mother to work, unawareness regarding milk extraction and preservation. The objective of this investigation is to evaluate the effect of storage time and temperature within a short term on how it affects the protein content in mature milk of mothers who attended medical consulting at Hospital Dr. Jorge Lizarraga. This is an experimental, correlational, cuantitative and applied investigation. Twenty milk samples were analyzed from healthy women with exclusive breastfeeding, obtained through manual extraction. Each of these samples was separated in 2 aliquots: 1. To be analyzed at once. 2. To be analyzed after being stored at 15°C for 24 hours. Determination of proteins was performed according to the industrial norms of Covenin. The concentration of proteins was of 1,53 gr/dl in recently extracted milk and 1,50 gr/dl in milk stored at 15°C for 24 hours. There was no significant difference between the values of proteins found in the recently extracted maternal milk and the one that had been stored

Feasibility of using flash-heated breastmilk as an infant feeding option for HIV-exposed, uninfected infants after 6 months of age in urban Tanzania.

OBJECTIVE: Heat-treating expressed breastmilk is recommended as an interim feeding strategy for HIV-exposed infants in resource-poor countries, but data on its feasibility are minimal. Flash-heating (FH) is a simple in-home technique for heating breastmilk that inactivates HIV although preserving its nutritional and anti-infective properties. Our primary objective was to determine, among HIV-infected mothers, the feasibility and protocol adherence of FH expressed breastmilk after 6 months of exclusive breastfeeding. DESIGN: Prospective longitudinal. PARTICIPANTS: One hundred one HIV-infected breastfeeding mothers. SETTING: Dar es Salaam, Tanzania. INTERVENTION: Peer counselors provided in-home counseling and support on infant feeding from 2 to 9 months postpartum. Mothers were encouraged to exclusively breastfeed for 6 months followed by FH expressed breastmilk if her infant was HIV negative. Clinic-based staff measured infant growth and morbidity monthly, and mothers kept daily logs of infant morbidity. FH behavior was tracked until 9 months postpartum using daily logs, in-home observations, and clinic-based and home-based surveys. Bacterial cultures of unheated and heated milk samples were performed. RESULTS: Thirty-seven of 72 eligible mothers (51.4%) chose to flash-heat. Median (range) frequency of milk expression was 3 (1-6) times daily and duration of method use on-study was 9.7 (0.1-15.6) weeks. Mean (SD) daily milk volume was 322 (201) mL (range 25-1120). No heated and 32 (30.5%) unheated samples contained bacterial pathogens. CONCLUSIONS: FH is a simple technology that many HIV-positive women can successfully use after exclusive breastfeeding to continue to provide the benefits of breastmilk while avoiding maternal-to-child transmission associated with nonexclusive breastfeeding. Based on these feasibility data, a clinical trial of the effects of FH breastmilk on infant health outcomes is warranted.

Effect of flash-heat treatment on antimicrobial activity of breastmilk.

BACKGROUND AND OBJECTIVES: The World Health Organization recommends human immunodeficiency virus (HIV)-positive mothers in resource-poor regions heat-treat expressed breastmilk during periods of increased maternal-to-child transmission risk. Flash-heat, a "low tech" pasteurization method, inactivates HIV, but effects on milk protein bioactivity are unknown. The objectives were to measure flash-heat's effect on antimicrobial properties of lactoferrin, lysozyme, and whole milk and on the digestive resistance of lactoferrin and lysozyme. METHODS: Flash-heated and unheated breastmilk aliquots from HIV-positive mothers in South Africa were "spiked" with Staphylococcus aureus and Escherichia coli and then cultured for 0, 3, and 6 hours. Lysozyme and lactoferrin activities were determined by lysis of Micrococcus luteus cells and inhibition of enteropathogenic E. coli, respectively, measured spectrophotometrically. Percentages of proteins surviving in vitro digestion, lactoferrin and lysozyme activity, and bacteriostatic activity of whole milk in heated versus unheated samples were compared. RESULTS: There was no difference in rate of growth of E. coli or S. aureus in flash-heated versus unheated whole milk (p = 0.61 and p = 0.96, respectively). Mean (95% confidence interval) antibacterial activity of lactoferrin was diminished 11.1% (7.8%, 14.3%) and that of lysozyme by up to 56.6% (47.1%, 64.5%) by flash-heat. Digestion of lysozyme was unaffected (p = 0.12), but 25.4% less lactoferrin survived digestion (p < 0.0001). CONCLUSIONS: In summary, flash-heat resulted in minimally decreased lactoferrin and moderately decreased lysozyme bioactivity, but bacteriostatic activity of whole milk against representative bacteria was unaffected. This suggests flash-heated breastmilk likely has a similar profile of resistance to bacterial contamination as that of unheated milk. Clinical significance of the decreased bioactivity should be tested in clinical trials.

Viability of infectious viral particles of HIV and BMCs in breast milk.

BACKGROUND: Infectious factors in breast milk such as viral particles and living infected cells are of prime importance in the transmission of HIV by breastfeeding. OBJECTIVES: To perform effective approaches for reducing HIV transmission via breastfeeding, we investigated the biological importance of infectious viral particles and infected BMCs in breast milk. STUDY DESIGN: Alteration of viral infectivity was monitored using a modified experimental infection assay that exploited the cytotoxicity of breast milk, and BMC viability was evaluated by flow-cytometric analysis. RESULTS: Infectious viral particles were found to decrease time-dependently after contact with breast milk, whereas BMCs showed prolonged survival in breast milk. CONCLUSIONS: The biological importance of infected BMCs in breast milk for the transmission of HIV via breastfeeding was considered.

[10 years after Chernobyl--radioactivity of mother's milk-- measurements from Tirol, Tibet and Nepal]. / 10 Jahre nach Tschernobyl--Strahlenbelastung der Muttermilch--Messungen aus Tirol, Tibet und Nepal.

10 years after the Chernobyl disaster gamma radioactivity from Cs-137 was determined in 53 breast milk samples from Tyrol, as well as 9 samples from Tibet and 2 from Nepal by means of a gamma-spectrometer with a germanium detector. In contrast to the values obtained within a few days, and again 1 year after the nuclear plant catastrophe, all samples from Tyrol showed gamma radioactivity levels (median 0.07 nCi/l; range 0.02-0.20 nCi/l) which were now below the limit laid down for baby food in Austria (0.3 nCi/l-11.1 Bq). The samples from Tibet and Nepal registered a slightly higher level of gamma radioactivity (median 0.16 nCi/l; range 0.16-0.41 nCi/l).

Radiation dose from breastfeeding following administration of thallium-201.

UNLABELLED: Radiation exposure to a breast feeding infant was estimated when the mother underwent a nuclear medicine procedure using 201Tl. METHODS: A lactating mother was administered 111 MBq of 201Tl for a brain scan. Breast milk samples were collected over a period of three days, and the rate of 201Tl secretion was determined. The infant was not breast fed during that time. Based on our data, we determined the time-activity function for radioactivity in the breast milk. From these data, and assuming an intake of 1000 ml/day, we calculated the fraction of administered activity that might be taken in by the infant. We also calculated the intake assuming breastfeeding delays of 2, 24, 48, 72, 96 and 500 hr. RESULTS: We calculated the radiation dose to various organs and the effective dose to an infant and a 1-yr-old for breastfeeding delays of 2 to 500 hr. The effective dose to a 1-yr-old from an administration of 111 MBq of 201Tl to the mother ranged from 0.90 mSv to 0.00072 mSv, and the effective dose to a newborn ranged from 1.6 mSv to 0.0013 mSv depending on delay time. CONCLUSION: Our estimates of radiation exposure to an infant from breastfeeding indicate that in this case, a 1-yr-old would have received less than the NCRP's proposed limit on annual effective dose to members of the general public of 1 mSv with a 48-hr delay and no restrictions on holding the child. A newborn would have received less than the proposed infrequent exposure limit of 5 mSv without any delay or restrictions in breastfeeding.

The effect of microwave heating on vitamins B1 and E, and linoleic and linolenic acids, and immunoglobulins in human milk.

Breast milk was treated with (1) conventional heating (in water bath) vs microwave heating; (2) microwave heating at two power levels (30% and 100%); (3) increasing final temperatures; and (4) microwave thawing vs refrigerator thawing and examined for changes in specific immunoglobulins to a pool of E. coli and poliovirus type 1 antigens, vitamins E and B1, and the polyunsaturated fatty acids linoleic and linolenic acid. Immunoglobulin activities were stable until final milk temperatures of around 60-65 degrees C were reached, and total inactivation occurred at 77 degrees C. Heating even to high final temperatures did not change contents of vitamins and polyunsaturated fatty acids. No differences in immunoglobulins and nutrients were demonstrated between microwave heating and conventional heating, and between power levels or thawing methods. The study shows that microwave heating of human milk can be performed without significant losses of examined immunoglobulins and nutrients, provided that final temperatures are below 60 degrees C.