1 00:00:00,920 --> 00:00:04,680 VOICE-OVER: Welcome to the ConsExpo Web tutorials for using models... 2 00:00:04,800 --> 00:00:08,920 to estimate consumer exposure by inhalation. 3 00:00:09,040 --> 00:00:11,280 In this introductory tutorial... 4 00:00:11,400 --> 00:00:17,240 you will learn the basics of ConsExpo Web’s inhalation exposure simulations... 5 00:00:17,360 --> 00:00:20,280 which are explained in four stages. 6 00:00:20,400 --> 00:00:24,840 The release of substances from consumer products to the air in a room... 7 00:00:24,960 --> 00:00:27,920 the dispersion of substances through the air... 8 00:00:28,040 --> 00:00:30,120 the inhalation of substances... 9 00:00:30,240 --> 00:00:35,240 and the absorption of inhaled substances into the human body. 10 00:00:35,360 --> 00:00:39,280 Basics of inhalation exposure simulations. 11 00:00:39,400 --> 00:00:46,280 All inhalation models included in ConsExpo Web consist of the same four stages. 12 00:00:46,400 --> 00:00:50,160 First, the substance is introduced into the air in a room... 13 00:00:50,280 --> 00:00:53,120 when released from a consumer product. 14 00:00:53,240 --> 00:00:56,480 Next, the substance is dispersed through the air. 15 00:00:56,600 --> 00:00:59,240 Here, the concentration of the substance in the air... 16 00:00:59,360 --> 00:01:04,280 can be simulated over different periods of time and under varying conditions... 17 00:01:04,400 --> 00:01:09,960 such as ventilation rate, room size or the amount released. 18 00:01:10,080 --> 00:01:14,120 The concentration of the substance in the air is considered to be equal... 19 00:01:14,240 --> 00:01:17,040 to the concentration of the substance in the air... 20 00:01:17,160 --> 00:01:19,400 that is inhaled by the consumer. 21 00:01:19,520 --> 00:01:25,040 Once the substance is inhaled, it may be absorbed into the human body. 22 00:01:25,160 --> 00:01:29,960 While these four stages apply to all ConsExpo Web inhalation models... 23 00:01:30,080 --> 00:01:35,000 ConsExpo Web has separate inhalation models for the release of substances... 24 00:01:35,120 --> 00:01:41,080 that evaporate from a liquid product, are sprayed into the room as droplets... 25 00:01:41,200 --> 00:01:44,000 or evaporate from solid materials. 26 00:01:45,520 --> 00:01:48,720 Release from consumer products. 27 00:01:48,840 --> 00:01:51,960 ConsExpo Web provides different evaporation modes... 28 00:01:52,080 --> 00:01:55,160 to estimate the release of substances into a room... 29 00:01:55,280 --> 00:01:57,680 depending on the product scenario. 30 00:01:57,800 --> 00:02:02,840 In cases where the evaluated substance evaporates from a liquid product... 31 00:02:02,960 --> 00:02:08,040 you should select the exposure to vapour mode for a simulation. 32 00:02:08,160 --> 00:02:11,800 In cases where the consumer uses an aerosol spray... 33 00:02:11,920 --> 00:02:16,560 and the evaluated substance is released into the air as sprayed droplets... 34 00:02:16,680 --> 00:02:20,560 you should select the exposure to spray mode. 35 00:02:20,680 --> 00:02:25,120 Lastly, ConsExpo Web is able to model the evaporation of a substance... 36 00:02:25,240 --> 00:02:29,360 from a product that consists of solid materials. 37 00:02:29,480 --> 00:02:33,480 Examples of cases where you should select the solid materials mode... 38 00:02:33,600 --> 00:02:37,840 are solid construction materials such as wood or limestone... 39 00:02:37,960 --> 00:02:40,080 that are impregnated with substances... 40 00:02:40,200 --> 00:02:44,120 that can evaporate over a prolonged period of time. 41 00:02:44,240 --> 00:02:47,200 All three release modes in ConsExpo Web... 42 00:02:47,320 --> 00:02:51,080 calculate the amount of a substance released over time. 43 00:02:51,200 --> 00:02:54,640 The ConsExpo Web user needs to select the release modes... 44 00:02:54,760 --> 00:02:59,320 that is most suitable for the specific consumer exposure scenario. 45 00:02:59,440 --> 00:03:02,240 ConsExpo Web has general input fields... 46 00:03:02,360 --> 00:03:06,080 that are used to simulate the inhalation exposure event... 47 00:03:06,200 --> 00:03:09,440 and are common to all three release modes. 48 00:03:09,560 --> 00:03:15,920 These general input fields will be explained in this introductory ConsExpo Web tutorial. 49 00:03:16,040 --> 00:03:20,360 The general input fields are in the scenario description... 50 00:03:20,480 --> 00:03:24,640 for example the frequency at which the consumer is exposed... 51 00:03:24,760 --> 00:03:30,040 scenario setting, such as the weight fraction of the substance in the product... 52 00:03:30,160 --> 00:03:35,000 the parameters needed for ConsExpo Web to simulate the dispersion through the air... 53 00:03:35,120 --> 00:03:39,240 such as the ventilation rate and the room volume... 54 00:03:39,360 --> 00:03:42,560 and finally the inhalation rate of the consumer... 55 00:03:42,680 --> 00:03:46,800 and the absorption of the substance upon inhalation. 56 00:03:46,920 --> 00:03:49,400 Dispersion through the air in the room. 57 00:03:49,520 --> 00:03:51,680 Room volume is an important parameter... 58 00:03:51,800 --> 00:03:55,880 for calculating the concentration of the substance in the air. 59 00:03:56,000 --> 00:03:58,320 The concentration in the air is calculated... 60 00:03:58,440 --> 00:04:01,920 by dividing the amount of substance present in the air... 61 00:04:02,040 --> 00:04:04,440 by the volume of air in the room. 62 00:04:04,560 --> 00:04:08,040 Therefore, the concentration in the air is inversely proportional... 63 00:04:08,160 --> 00:04:10,200 to the volume of the room. 64 00:04:10,320 --> 00:04:15,000 Another important parameter required to calculate the concentration in the air... 65 00:04:15,120 --> 00:04:17,840 is the ventilation rate of the room. 66 00:04:17,960 --> 00:04:20,480 The concentration of a substance in the air... 67 00:04:20,600 --> 00:04:24,360 is inversely proportional to the ventilation rate. 68 00:04:24,480 --> 00:04:29,680 ConsExpo Web requires a ventilation rate expressed 'per hour'. 69 00:04:29,800 --> 00:04:34,120 This refers to the number of air changes per hour in the room. 70 00:04:34,240 --> 00:04:36,720 One way to calculate the ventilation rate... 71 00:04:36,840 --> 00:04:41,640 is to divide the volume of air leaving the room per hour by the room volume. 72 00:04:41,760 --> 00:04:46,680 For instance, if it takes two hours for a complete change of air in the room... 73 00:04:46,800 --> 00:04:50,360 the ventilation rate is 0.5 per hour. 74 00:04:51,080 --> 00:04:55,240 Since room volume and ventilation rate are general input parameters... 75 00:04:55,360 --> 00:04:56,880 of ConsExpo Web... 76 00:04:57,000 --> 00:04:59,120 you may consult the general fact sheet... 77 00:04:59,240 --> 00:05:04,880 to obtain the appropriate value for your specific consumer exposure scenario. 78 00:05:05,000 --> 00:05:09,000 Here is an overview of the type of rooms described in the general fact sheet... 79 00:05:09,120 --> 00:05:14,680 with their respective default room volumes and derived ventilation rates. 80 00:05:14,800 --> 00:05:16,880 Here you see how a graph can be displayed... 81 00:05:17,000 --> 00:05:20,040 that shows the concentration in the air over time... 82 00:05:20,160 --> 00:05:25,360 calculated by ConsExpo Web in an inhalation exposure simulation. 83 00:05:25,480 --> 00:05:28,840 You can find graphs like this one on the 'Graphs' tab. 84 00:05:28,960 --> 00:05:32,520 We use it here to explain the output of ConsExpo Web... 85 00:05:32,640 --> 00:05:35,480 regarding concentrations in the air. 86 00:05:35,600 --> 00:05:37,560 The mean event concentration refers... 87 00:05:37,680 --> 00:05:40,760 to the mean concentration of the substance in the room... 88 00:05:40,880 --> 00:05:44,480 over the entire duration of the exposure event. 89 00:05:44,600 --> 00:05:51,840 In this graph, the mean concentration over 100 minutes is 5.5 mg/m3... 90 00:05:51,960 --> 00:05:57,440 which is the same as the mean event concentration found on the 'Results' tab. 91 00:05:57,560 --> 00:06:01,880 ConsExpo Web also calculates a peak concentration. 92 00:06:02,000 --> 00:06:05,720 This peak concentration refers to those 15 minutes... 93 00:06:05,840 --> 00:06:10,760 over which the air concentration is the highest within the exposure duration. 94 00:06:10,880 --> 00:06:13,680 This peak concentration is therefore also known... 95 00:06:13,800 --> 00:06:17,920 as the time-weighted average concentration for 15 minutes... 96 00:06:18,040 --> 00:06:23,480 or the 'TWA 15 min' for short. 97 00:06:23,600 --> 00:06:26,680 'Mean concentration on day of exposure'... 98 00:06:26,800 --> 00:06:30,520 refers to the mean concentration in the air of the substance... 99 00:06:30,640 --> 00:06:34,640 over the entire 24 hours of the day of product use. 100 00:06:34,760 --> 00:06:38,680 As such, the mean concentration on the day of exposure... 101 00:06:38,800 --> 00:06:42,360 is actually the same as the mean event concentration... 102 00:06:42,480 --> 00:06:48,800 multiplied by the usage frequency per day and divided by 24 hours. 103 00:06:48,920 --> 00:06:53,440 The same principle applies to 'Year average concentration'... 104 00:06:53,560 --> 00:06:56,600 which is the same as the mean event concentration... 105 00:06:56,720 --> 00:07:04,000 multiplied by the usage frequency per year and divided by 365 days. 106 00:07:04,120 --> 00:07:06,080 Inhalation. 107 00:07:06,200 --> 00:07:09,800 The inhalation rate and exposure duration... 108 00:07:09,920 --> 00:07:13,240 are general inputs that ConsExpo Web needs... 109 00:07:13,360 --> 00:07:17,680 to calculate the amount of the substance inhaled by the consumer. 110 00:07:17,800 --> 00:07:23,560 In an inhalation exposure scenario, the consumer breaths in the air. 111 00:07:23,680 --> 00:07:27,320 ConsExpo Web simulates the concentration of the substance... 112 00:07:27,440 --> 00:07:28,920 in the inhaled air... 113 00:07:29,040 --> 00:07:33,080 by treating it the same as the concentration in the room air. 114 00:07:33,200 --> 00:07:39,240 The respiratory tract of the consumer is then exposed to the evaluated substance. 115 00:07:39,360 --> 00:07:42,720 ConsExpo Web has a button that users can click... 116 00:07:42,840 --> 00:07:47,840 to calculate an inhalation rate as a function of a consumer's body weight... 117 00:07:47,960 --> 00:07:50,520 as specified in the earlier assessment settings... 118 00:07:50,640 --> 00:07:55,160 and the intensity of the exercise performed by the consumer. 119 00:07:55,280 --> 00:08:02,400 The default exercise types are sleep, rest, light and heavy exercise. 120 00:08:02,520 --> 00:08:06,240 ConsExpo Web users can select the level of exercise... 121 00:08:06,360 --> 00:08:10,160 that is most appropriate for the consumer exposure scenario... 122 00:08:10,280 --> 00:08:13,280 in the calculator settings menu. 123 00:08:13,400 --> 00:08:17,760 The results that ConsExpo Web provides for the inhalation scenarios... 124 00:08:17,880 --> 00:08:26,120 are expressed as 'external event dose' and 'external event dose on day of exposure'. 125 00:08:26,240 --> 00:08:29,480 The external event dose refers to the amount of substance... 126 00:08:29,600 --> 00:08:33,280 inhaled by the consumer during the exposure event... 127 00:08:33,400 --> 00:08:37,120 which is equal to the product of the mean event concentration... 128 00:08:37,240 --> 00:08:43,000 inhalation rate and exposure duration divided by the consumer's body weight. 129 00:08:43,120 --> 00:08:46,000 The external event dose on the day of exposure... 130 00:08:46,120 --> 00:08:52,400 is equal to the external event dose multiplied by the usage frequency per day. 131 00:08:52,520 --> 00:08:53,840 Absorption. 132 00:08:53,960 --> 00:08:56,080 Absorption refers to the process... 133 00:08:56,200 --> 00:09:00,920 by which a substance enters the human body as a result of exposure. 134 00:09:01,040 --> 00:09:04,720 In the inhalation exposure scenarios, this refers to the dose... 135 00:09:04,840 --> 00:09:10,120 that is absorbed by the respiratory tract upon inhalation of a substance. 136 00:09:10,240 --> 00:09:13,800 In ConsExpo Web, the absorbed substance amount... 137 00:09:13,920 --> 00:09:18,960 is estimated using a fraction that is inserted as a fixed value. 138 00:09:19,080 --> 00:09:22,440 If, for example, the user enters a fraction of 50%... 139 00:09:22,560 --> 00:09:25,640 ConsExpo Web will calculate the exposure... 140 00:09:25,760 --> 00:09:29,200 assuming that 50% of the inhaled substance amount... 141 00:09:29,320 --> 00:09:34,640 is absorbed into the human body and the remaining 50% is exhaled. 142 00:09:34,760 --> 00:09:40,200 Next, the internal event dose is derived by multiplying the external event dose... 143 00:09:40,320 --> 00:09:42,640 by the absorption fraction. 144 00:09:42,760 --> 00:09:47,120 Similarly, the internal year average dose is the external event dose... 145 00:09:47,240 --> 00:09:52,920 multiplied by the absorption fraction and the product usage frequency per year. 146 00:09:53,040 --> 00:09:55,920 In summary, this tutorial explained the basics... 147 00:09:56,040 --> 00:10:00,880 of how ConsExpo Web simulates inhalation exposure. 148 00:10:01,000 --> 00:10:03,680 Thank you for listening to the introductory tutorial... 149 00:10:03,800 --> 00:10:07,000 on ConsExpo Web inhalation modelling. 150 00:10:07,120 --> 00:10:11,200 We would like to acknowledge our partners: Health Canada... 151 00:10:11,320 --> 00:10:16,680 the French Agency for Food, Environmental and Occupational Health & Safety... 152 00:10:16,800 --> 00:10:20,240 the German Federal Institute for Risk Assessment... 153 00:10:20,360 --> 00:10:23,440 the Swiss Federal Office of Public Health... 154 00:10:23,560 --> 00:10:27,280 the Netherlands Food and Consumer Product Safety Authority... 155 00:10:27,400 --> 00:10:31,400 and the Dutch Ministry of Health, Welfare and Sport.